UPDATE 1-U.S.-based stock funds attract $9.9 bln in latest week - Lipper

(Adds additional flows, analyst comment, table) By Sam Forgione NEW YORK, Aug 21 (Reuters) - Risk appetite made a raging comeback with investors pouring $2.2 billion into high-yield junk bond funds and $9.9 billion into stock funds in the week ended Aug. 20, data from Thomson Reuters' Lipper service showed on Thursday. The inflows into high-yield bond funds were the biggest since last September and marked their second straight week of new money, while the inflows into stock funds we