8X8, Inc.
NOTES TO UNAUDITED CONSOLIDATED FINANCIAL STATEMENTS

A provider of enterprise cloud communications solutions, 8x8, Inc. (8x8 or the Company) helps businesses get their employees, customers and applications more connected and productive worldwide. From one technology platform, the Company offers cloud phone, collaboration, conferencing, contact center, data analytics and other services to business customers on a Software-as-a-Service (SaaS) model. The Company's solutions offer a secure, reliable and simplified approach for businesses to transition their legacy, on-premises communications systems to the cloud. The comprehensive solution, built from owned core cloud technologies, enables 8x8 customers to rely on a single provider for their global communications, contact center and customer support requirements. Combining these services allows customers to eliminate information silos and expose vital, real-time communications data spanning multiple services, applications and devices which, in turn, can improve productivity, business performance and customer experience. The Company's customers are spread across more than 150 countries and range from small businesses to large enterprises with more than 10,000 employees.

The Company's fiscal year ends on March 31 of each calendar year. Each reference to a fiscal year in these notes to the consolidated financial statements refers to the fiscal year ended March 31 of the calendar year indicated (for example, fiscal 2019 refers to the fiscal year ending March 31, 2019).

The accompanying interim consolidated financial statements are unaudited and have been prepared on substantially the same basis as our annual consolidated financial statements for the fiscal year ended March 31, 2018, with the exception of new revenue recognition guidance discussed in the recently adopted accounting principles section below. Certain information and note disclosures normally included in the financial statements prepared in accordance with GAAP have been condensed or omitted pursuant to the rules and regulations of the Securities and Exchange Commission (SEC), regarding interim financial reporting.

In the opinion of the Company's management, these interim consolidated financial statements reflect all adjustments (consisting only of normal recurring adjustments) considered necessary for a fair statement of our financial position, results of operations, and cash flows for the periods presented. The preparation of financial statements in conformity with generally accepted accounting principles requires management to make estimates and assumptions that affect the reported amounts of assets, liabilities, disclosure of contingent assets and liabilities at the date of the consolidated financial statements, and the reported amounts of revenue and expenses during the reporting periods. Actual results could differ from these estimates.

The March 31, 2018 year-end consolidated balance sheet data in this document were derived from audited consolidated financial statements and does not include all of the disclosures required by U.S. generally accepted accounting principles. These consolidated financial statements should be read in conjunction with the Company's audited consolidated financial statements as of and for the fiscal year ended March 31, 2018 and notes thereto included in the Company's fiscal 2018 Annual Report on Form 10-K.

The results of operations and cash flows for the interim periods included in these consolidated financial statements are not necessarily indicative of the results to be expected for any future period or the entire fiscal year.

The consolidated financial statements include the accounts of 8x8 and its subsidiaries. All material intercompany accounts and transactions have been eliminated.

In April 2018, the Company entered into an asset purchase agreement with MarianaIQ, Inc. The total aggregate purchase price consisted of cash paid at closing and cash deposited into escrow to be held for fifteen months as security against indemnity claims made by the Company after the closing date. See Note 11 for additional information.

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USE OF ESTIMATES

The preparation of the consolidated financial statements in conformity with accounting principles generally accepted in the United States requires management to make estimates and assumptions that affect the reported amounts of assets, liabilities and equity and disclosure of contingent assets and liabilities at the date of the consolidated financial statements and the reported amounts of revenues and expenses during the reporting period. On an ongoing basis, the Company evaluates its estimates, including, but not limited to, those related to bad debts, returns reserve for expected cancellations, income and sales tax liabilities, stock-based compensation, and litigation and other contingencies. The Company bases its estimates on historical experience and on various other assumptions. Actual results could differ from those estimates under different assumptions or conditions.

The significant accounting policies used in preparation of these consolidated financial statements are disclosed in our Annual Report on Form 10-K for the fiscal year ended March 31, 2018 filed with the SEC on May 30, 2018, and there have been no changes to the Company's significant accounting policies during the three months ended September 30, 2018 except for the accounting policies described below that were updated as a result of adopting Accounting Standards Update (ASU) 2014-9, Revenue from Contracts with Customers: Topic 606 (ASU 2014-9 or ASC 606). ASU 2014-9 also included Subtopic 340-40, Other Assets and Deferred Costs - Contracts with Customers, which sets forth the requirement of deferring incremental costs of obtaining a contract with a customer. All amounts and disclosures set forth herein are in compliance with these standards.

In May 2014, the Financial Accounting Standards Board (FASB) issued ASU 2014-9, which replaces numerous requirements in U.S. GAAP and provide companies with a single revenue recognition model for recognizing revenue from contracts with customers. ASC 606 requires an entity to recognize the amount of revenue to which it expects to be entitled for the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. It defines a five-step process to achieve this core principle and, in doing so, more judgment and estimates are required with the revenue recognition process than were required under the previous guidance (ASC 605).

The new standard permits the use of either the full retrospective or modified retrospective transition method. The Company adopted the new standard effective April 1, 2018 using the modified retrospective method. Under the modified retrospective method, the comparative periods' information is not restated and continues to be reported under the accounting standards in effect in those prior periods. Instead, on April 1, 2018, the Company recognized the cumulative effect of initially applying ASC 606 as an adjustment to the opening balance of accumulated deficit and the corresponding balance sheet accounts, which resulted in a net decrease to accumulated deficit of $39.9 million. The impact on the Company's opening balances primarily relates to the capitalization of additional commission costs under ASC 606 in the amount of $38.2 million.   Under ASC 605, the Company expensed all commission costs as incurred. Under ASC 606, the Company defers all incremental commission costs to obtain the contract and amortizes these costs over a benefit period of five years. The remaining $1.7 million impact of adopting the standard relates to revenue being recognized earlier under ASC 606 than it would have been under ASC 605, which resulted in a contract asset as of the adoption date.

See Note 2 for additional disclosure on the impact of adopting this standard.

In February 2016, the FASB issued ASU 2016-2, Leases (Topic 842), along with amendments issued in 2018, which requires companies to generally recognize on the balance sheet operating and financing lease liabilities and corresponding right-of-use assets. The update also requires qualitative and quantitative disclosures designed to assess the amount, timing, and uncertainty of cash flows arising from leases.  The update requires the use of a modified retrospective transition approach, which includes a number of optional practical expedients that entities may elect to apply. This amendment is effective for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years. Early adoption is permitted. The Company is currently assessing the impact of this pronouncement to its consolidated financial statements.

In June 2018, the FASB issued ASU 2018-7, Compensation-Stock Compensation (Topic 718), which now provides guidance for share-based payments to non-employees, resulting in alignment in accounting for employees and non-employees. The amendment is effective for public companies with fiscal years beginning after December 15, 2018. Early adoption is permitted. The Company is currently assessing the impact of this pronouncement to its consolidated financial statements.

In August 2018, the FASB issued ASU 2018-13, Fair Value Measurement (Topic 820), which makes modifications to disclosure requirements on fair value measurements. The amendment is effective for public companies with fiscal years beginning after December 15, 2019. Early adoption is permitted. The Company is currently assessing the impact of this pronouncement to its consolidated financial statements.

In August 2018, the FASB issued 2018-15, Intangibles-Goodwill and Other-Internal Use Software (Subtopic 350-40), which reduces complexity for the accounting for the accounting for costs of implementing a cloud computing service arrangement. The amendment is effective for public companies with fiscal years beginning after December 15, 2019. Early adoption is permitted. The Company is currently assessing the impact of this pronouncement to its consolidated financial statements.

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2. REVENUE RECOGNITION

The Company recognizes service revenue, mainly from subscription services to its cloud-based voice, call center, video and collaboration solutions using the five-step model as prescribed by ASC 606:

• Identification of the contract, or contracts, with a customer;
• Identification of the performance obligations in the contract;
• Determination of the transaction price;
• Allocation of the transaction price to the performance obligations in the contract; and
• Recognition of revenue when or as, the Company satisfies a performance obligation.

The Company identifies performance obligations in contracts with customers, which may include subscription services and related usage, product revenue and professional services. The transaction price is determined based on the amount the Company expects to be entitled to in exchange for transferring the promised services or products to the customer. The transaction price in the contract is allocated to each distinct performance obligation in an amount that represents the relative amount of consideration expected to be received in exchange for satisfying each performance obligation. Revenue is recognized when performance obligations are satisfied. Revenues are recorded based on the transaction price excluding amounts collected on behalf of third parties such as sales and telecommunication taxes, which are collected on behalf of and remitted to governmental authorities. The Company usually bills its customers on a monthly basis. Contracts typically range from annual to multi-year agreements with payment terms of net 30 days or less. The Company occasionally allows a 30-day period to cancel a subscription and return products shipped for a full refund.

The estimation of variable consideration for each performance obligation requires the Company to make subjective judgments. The Company has service-level agreements with customers warranting defined levels of uptime reliability and performance. Customers may get credits or refunds if the Company fails to meet such levels. If the services do not meet certain criteria, fees are subject to adjustment or refund representing a form of variable consideration. The Company may impose minimum revenue commitments (MRC) on its customers at the inception of the contract. Thus, in estimating variable consideration for each of these performance obligations, the Company assesses both the probability of MRC occurring and the collectability of the MRC, of which both represent a form of variable consideration.

The Company enters into contracts with customers that regularly include promises to transfer multiple services and products, such as subscriptions, products, and professional services. For arrangements with multiple services, the Company evaluates whether the individual services qualify as distinct performance obligations. In its assessment of whether a service is a distinct performance obligation, the Company determines whether the customer can benefit from the service on its own or with other readily available resources, and whether the service is separately identifiable from other services in the contract. This evaluation requires the Company to assess the nature of each individual service offering and how the services are provided in the context of the contract, including whether the services are significantly integrated, highly interrelated, or significantly modify each other, which may require judgment based on the facts and circumstances of the contract.

When agreements involve multiple distinct performance obligations, the Company allocates arrangement consideration to all performance obligations at the inception of an arrangement based on the relative standalone selling prices (SSP) of each performance obligation. Usage fees deemed to be variable consideration meet the allocation exception for variable consideration. Where the Company has standalone sales data for its performance obligations which are indicative of the price at which the Company sells a promised good or service separately to a customer, such data is used to establish SSP. In instances where standalone sales data is not available for a particular performance obligation, the Company estimates SSP by the use of observable market and cost-based inputs. The Company continues to review the factors used to establish list price and will adjust standalone selling price methodologies as necessary on a prospective basis.

Service revenue from subscriptions to the Company's cloud-based technology platform is recognized over time on a ratable basis over the contractual subscription term beginning on the date that the platform is made available to the customer. Payments received in advance of subscription services being rendered are recorded as a deferred revenue. Usage fees, either bundled or not bundled, are recognized when the Company has a right to invoice. Professional services for configuration, system integration, optimization, customer training and/or education are primarily billed on a fixed-fee basis and are performed by the Company directly or, alternatively, customers may also choose to perform these services themselves or engage their own third-party service providers. Professional services revenue is recognized over time, generally as customer sites go live.

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When a contract with a customer is signed, the Company assesses whether collection of the fees under the arrangement is probable. The Company estimates the amount to reserve for uncollectible amounts based on the aging of the contract balance, current and historical customer trends, and communications with its customers. These reserves are recorded as operating expenses against the contract asset (Accounts Receivable). In the normal course of business, the Company records revenue reductions for customer credits.

The Company recognizes product revenue for telephony equipment at a point in time, when transfer of control has occurred, which is generally upon shipment. Sales returns are recorded as a reduction to revenue estimated based on historical experience.

Contract assets are recorded for those parts of the contract consideration not yet invoiced but for which the performance obligations are completed. The revenue is recognized when the customer receives services or equipment for a reduced consideration at the onset of an arrangement, for example when the initial month's services or equipment are discounted. Contract assets are included in other current or non-current assets in the consolidated balance sheets, depending on if their reduction is recognized during the succeeding 12-month period or beyond.

Deferred revenues represent billings or payments received in advance of revenue recognition and is recognized upon transfer of control. Balances consist primarily of annual plan subscription services and professional and training services not yet provided as of the balance sheet date. Deferred revenues that will be recognized during the succeeding 12-month period are recorded as current deferred revenues in the consolidated balance sheets, with the remainder recorded as other non-current liabilities in the consolidated balance sheets.

Sales commissions and related expenses are considered incremental and recoverable costs of acquiring customer contracts. These costs are capitalized as other current or non-current assets and amortized on a straight-line basis over the anticipated benefit period, which is five years. The benefit period was estimated by taking into consideration the length of customer contracts, technology lifecycle, and other factors. This amortization expense is recorded in sales and marketing expense within the Company's consolidated statement of operations.

The new guidance under ASC 340-40, Other Assets and Deferred Costs - Contracts with Customers, sets forth the requirement of deferring incremental costs of obtaining a contract, typically sales commissions, that were expensed as incurred under the previous guidance. The Company applies a practical expedient that permits to apply Subtopic 340-40 to a portfolio of contracts, instead of on a contract-by-contract basis, as they are similar in their characteristics, and the financial statement effects of applying Subtopic 340-40 to that portfolio would not differ materially from applying it to the individual contracts within that portfolio.

The Company recognized the cumulative effect of initially applying ASC 606 as an adjustment to retained earnings in the consolidated balance sheet as of April 1, 2018 (in thousands).

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The following tables summarize the impact of the ASC 606 adoption on the Company's consolidated financial statements for the quarter ended September 30, 2018.

The Company disaggregates its revenue by geographic region. See Note 10 for more information.

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Contract Balances

The following table provides information about receivables, contract assets and deferred revenues from contracts with customers (in thousands):

Changes in the contract assets and the deferred revenue balances during the six months ended September 30, 2018 are as follows (in thousands):

The change in contract assets was primarily driven by the recognition of revenue that has not yet been billed. The increase in deferred revenues was due to billings in advance of performance obligations being satisfied. During the three and six months ended September 30, 2018, $1.8 million and $3.2 million, respectively, of revenue recognized was included in the deferred revenues balance at the beginning of the period, which was offset by additional deferrals during the period.

The Company's subscription terms typically range from one to four years. Contract revenue as of September 30, 2018, that has not yet been recognized was approximately $140 million. This excludes contracts with an original expected length of one year or less. The Company expects to recognize revenue on the vast majority of the remaining performance obligation over the next 24 months.

Cash, cash equivalents, and available-for-sale investments (in thousands):

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Contractual maturities of investments as of September 30, 2018 are set forth below (in thousands):

The carrying value of intangible assets consisted of the following (in thousands):

At September 30, 2018, annual amortization of intangible assets, based upon our existing intangible assets and current useful lives, is estimated to be the following (in thousands):

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5. GOODWILL

The following table provides a summary of the changes in the carrying amounts of goodwill by reporting segment (in thousands):

The Company leases its headquarter's office space in San Jose, California, and also leases office space under non-cancelable operating leases in various domestic and international locations. During the first quarter of fiscal 2019, as it took control of its new corporate headquarters to begin the build out, the Company began to record additional rent expenses on a straight-line basis. Total rent expense for the three and six months ended September 30, 2018 was $2.6 million and $5.3 million, respectively. Total rent expense for the three and six months ended September 30, 2017 was $1.4 million and $2.8 million, respectively. Future minimum annual lease payments as of September 30, 2018 were as follows (in thousands):

The Company has entered into a series of noncancelable capital lease agreements for data center and office equipment bearing interest at various rates.

From time to time, the Company receives inquiries from various state and municipal taxing agencies with respect to the remittance of sales, use, telecommunications, excise, and income taxes. Several jurisdictions currently are conducting tax audits of the Company's records. The Company collects or has accrued for taxes that it believes are required to be remitted. The amounts that have been remitted have historically been within the accruals established by the Company. The Company adjusts its accrual when facts relating to specific exposures warrant such adjustment.

During the second quarter of fiscal 2019, the Company determined that additional sales taxes were probable of being assessed and estimable in multiple states as a result of preliminary findings from current sales and use tax audits. As a result, the Company estimated an incremental sales tax liability of $4.6 million, which was recorded as general and administrative expense in the consolidated statements of operations in the second quarter of fiscal 2019.

The Company, from time to time, is involved in various legal claims or litigation, including patent infringement claims that can arise in the normal course of the Company's operations. Pending or future litigation could be costly, could cause the diversion of management's attention and could upon resolution, have a material adverse effect on the Company's business, results of operations, financial condition and cash flows.

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7. STOCK-BASED COMPENSATION

The following tables summarize information pertaining to the stock-based compensation expense from stock options and stock awards (in thousands, except weighted-average grant-date fair value and recognition period):

In May 2017, the Company's board of directors authorized the Company to purchase up to $25.0 million of its common stock from time to time under the 2017 Repurchase Plan (the "2017 Plan"). The 2017 Plan expires when the maximum purchase amount is reached, or upon the earlier revocation or termination by the board of directors. The remaining amount available under the 2017 Plan at September 30, 2018 was approximately $7.1 million. There were no stock repurchases under the 2017 Plan during the six months period ended September 30, 2018.

The Company's effective tax rate was (1)% and 86% for the three months ended September 30, 2018 and 2017, respectively. The effective tax rate is calculated by dividing the income tax provision by net income (loss) before income tax expense. The difference in the effective tax rate and the U.S. federal statutory rate was due primarily to the change in pretax profitability, and geographic mix of profits and losses and the full valuation allowance recorded during the third quarter of fiscal year 2018.

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9. NET LOSS PER SHARE

The following table summarizes the computation of basic and diluted net loss per share (in thousands, except share and per share data):

The following shares attributable to outstanding stock options and stock awards were excluded from the calculation of diluted earnings per share because their inclusion would have been anti-dilutive (in thousands):

The Company manages its operations primarily on a geographic basis. The Company's reportable segments are the Americas and Europe. The Americas segment is primarily North America. The Europe segment is primarily the United Kingdom.

The following tables set forth the segment and geographic information for each period (in thousands):

Revenues are attributed to each segment based on the ordering location of the customer or ship to location. For the three and six months ended September 30, 2018 and 2017, inter-segment revenues of approximately $6.5 million and $13.1 million, and $4.4 million and $6.9 million respectively, were eliminated in consolidation, and have been excluded from the table above.

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On April 12, 2018, the Company entered into an Asset Purchase Agreement with MarianaIQ Inc. (MarianaIQ) for the purchase of certain assets of MarianaIQ. The total aggregate purchase price consisted of cash paid to MarianaIQ at closing, and cash to be held in escrow by the Company for fifteen months, as security against indemnity claims asserted by the Company after the closing date. The escrow amount is recorded as other accrued liabilities on the consolidated balance sheets as of September 30, 2018.

The Company recorded the acquired developed technology as an identifiable intangible asset with an estimated useful life of two years. The fair value of the technology was based on estimates and assumptions made by management using a cost approach method. The intangible asset is amortized on a straight-line basis over two years.

The excess of the consideration transferred over the aggregate fair value of the asset acquired was recorded as goodwill. The amount of goodwill recognized was primarily attributable to the expected contributions of the entity to the overall corporate strategy in addition to the acquired workforce.

The preliminary fair values of the assets acquired are as follows (in thousands):

MarianaIQ did not contribute materially to revenue or net loss for the period of acquisition to September 30, 2018. Goodwill recognized upon acquisition is expected to be deductible for income tax purposes and is included in the Americas reporting unit (see Note 5). Total acquisition costs were immaterial.

On October 26, 2018, the Company entered into an Asset Purchase Agreement with Atlassian Corporation Plc. (Atlassian) through which the Company purchased certain assets from Atlassian relating to the Jitsi open source video communications technology (Jitsi). The Company intends to integrate Jitsi's video collaboration capabilities into 8x8's technology platform to further enhance the Company's video and X Series platform offerings.

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ITEM 2. MANAGEMENT'S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS

This Management Discussion and Analysis of Financial Condition and Results of Operations contains forward-looking statements within the meaning of Section 27A of the Securities Act and Section 21E of the Exchange Act. Any statements contained herein that are not statements of historical fact may be deemed to be forward-looking statements. For example, words such as "may," "will," "should," "estimate," "predict," "potential," "continue," "strategy," "believe," "anticipate," "plan," "expect," "intend," and similar expressions are intended to identify forward-looking statements. You should not place undue reliance on these forward-looking statements. Actual results and trends may differ materially from historical results or those projected in any such forward-looking statements depending on a variety of factors. These factors include, but are not limited to - market acceptance of new or existing services and features, customer acceptance and demand for our cloud communication and collaboration services, changes in the competitive dynamics of the markets in which we compete, the quality and reliability of our services, customer cancellations and rate of churn, our ability to scale our business, customer acquisition costs, our reliance on infrastructure of third-party network services providers, risk of failure in our physical infrastructure, risk of failure of our software, our ability to maintain the compatibility of our software with third-party applications and mobile platforms, continued compliance with industry standards and regulatory requirements in the United States and foreign countries in which we make our software solutions available, and the costs of such compliance, risks relating to our strategies and objectives for future operations, including the execution of integration plans and realization of the expected benefits of our acquisitions, the amount and timing of costs associated with recruiting, training and integrating new employees, timing and extent of improvements in operating results from increased spending in marketing, sales, and research and development, timing and extent and outcome of sales and utility tax audits, introduction and adoption of our cloud software solutions in markets outside of the United States, risk of cybersecurity breaches, general economic conditions that could adversely affect our business and operating results, implementation and effects of new accounting standards and policies in our reported financial results, and potential future intellectual property infringement claims and other litigation that could adversely affect our business and operating results.

All forward-looking statements included in this report are based on information available to us on the date hereof, and we assume no obligation to update any such forward-looking statements. In addition to the factors discussed elsewhere in this Form 10-Q, see the Risk Factors discussion in Item 1A of our 2018 Form 10-K. The forward-looking statements included in this Form 10-Q are made only as of the date of this report, and we undertake no obligation to update the forward-looking statements to reflect subsequent events or circumstances.

A provider of enterprise cloud communications solutions, 8x8 helps businesses get their employees, customers and applications more connected and productive worldwide. From one technology platform, we offer cloud phone, collaboration, conferencing, contact center, data analytics and other services to business customers on a Software-as-a-Service (SaaS) model. Our solutions offer a secure, reliable and simplified approach for businesses to transition their legacy, on-premises communications systems to the cloud. Our comprehensive solution, built from core cloud technologies that we own and manage internally, enables 8x8 customers to rely on a single provider for their global communications, contact center and customer support requirements. Combining these services allows our customers to eliminate information silos and expose vital, real-time communications data spanning multiple services, applications and devices which, in turn, can improve productivity, business performance and customer experience. Our customers are spread across more than 150 countries and range from small businesses to large enterprises with more than 10,000 employees. In recent years, we have increased our focus on the mid-market and enterprise customer segments, and in fiscal 2018, we generated a majority of our new services revenue from customers in these business segments.

In the second quarter of fiscal 2019, our service revenue from mid-market and enterprise customers grew 30% year-over year and represented 61% of total service revenue. Average monthly service revenue per mid-market and enterprise business customer (ARPU) increased 6% to a record $4,988, compared with $4,697 in the same period last year. The increase resulted from our success in selling a greater number of new subscriptions to larger customers.

In July 2018, we announced general availability of the 8x8 X Series -- a single cloud platform which delivers a system of intelligence for voice, video conferencing, contact center, team messaging and collaboration across mobile and desktop devices. The 8x8 X Series is available in the U.S. and U.K. with multiple plans from X1 to X8 to meet different business needs for our small, mid-market and enterprise customers.

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In September 2018, we integrated Team Messaging into the 8x8 X Series solution. Team Messaging enables business units, project teams, and internal and external collaborators to share content and communicate as a team by providing instant access for all employees through a direct connection to your global directory. Furthermore, 8x8 Team Messaging allows full interoperability with almost two dozen third-party team messaging platforms, including Slack.

In October 2018, we announced the acquisition of Jitsi, an open source video collaboration technology from Atlassian. Jitsi further extends 8x8's cloud technology platform with highly scalable video routing and interoperability capabilities, all built on industry standards such as webRTC. Jitsi's open-source technology and team of video technology personnel will play a role in leading development of new X Series capabilities, including dedicated video collaboration applications and WebRTC, which will further enhance our 8x8 Meetings solution.

We intend to continue to invest in talent, marketing and demand generation activities, product innovation and the global expansion of the X Series for the remainder of fiscal 2019. We expect our operating expenses to grow materially as we continue to invest in accelerating revenue growth. In achieving these objectives, we face many risks, including those described under "RISK FACTORS", disclosed below and in our Form 10-K for the fiscal year ended March 31, 2018.

RESULTS OF OPERATIONS

The following discussion should be read in conjunction with our consolidated financial statements and the notes thereto.

Service revenue consists primarily of our cloud communication and collaboration subscription services, and to a lesser extent, usage and professional services fees.

Service revenues increased for the three and six months ended September 30, 2018 compared with the same period of the previous fiscal year primarily due to an increase in our business customer subscriber base (net of customer churn), and an increase in the average monthly service revenue per customer. Average monthly service revenue per customer increased from $442 at September 30, 2017 to $490 at September 30, 2018.

We expect growth in the number of customers and average monthly service revenue per customer to continue for the remainder of fiscal 2019.