Economic concerns weighed the markets down to a lower close with the Dow tumbling 99 points to 17,651. Nasdaq dropped 37 points to 4,725.

On the upside

Gol Linhas (NYSE: GOL) commenced a private exchange offering.

Quad/Graphics (NYSE: QUAD) swung to a profit for the first quarter.

Bargain hunters lifted shares of Archrock (NYSE: AROC).

On the downside

Big 5 Sporting Goods (Nasdaq: BGFV) fell to a greater than expected loss for the first quarter.

Raymond James downgraded AMAG Pharmaceuticals (Nasdaq: AMAG) from an Outperform rating to a Market Perform rating.

Kynikos Associates founder Jim Chanos said that SolarCity (Nasdaq: SCTY) would face financial trouble this year.

In the broad market, declining issues outpaced advancers by a margin of 3 to 2 on the NYSE and by nearly 2 to 1 on Nasdaq. The broader S&P 500 lost 12 points to 2,051. Bitcoin fell $3 to $444.