Before the bell Wednesday, analysts forecast that pharmaceutical company Merck & Co., Inc. (NYSE: MRK) will announce decreased profits with earnings per share down 20 percent from a year ago. Analysts surveyed by Thomson Reuters are projecting Merck to report earnings of 79 cents per share, down from 99 cents a year ago. Although the Zachs consensus estimate for Comcast Corporation (Nasdaq: CMCSA) has fallen from 50 cents to earnings of 49 cents a share, it's still an increase of almost 9 percent from the year-ago quarter.Also on Wednesday, Wall Street is optimistic about Time Warner Inc. (NYSE:TWX) as the company is expected to book a profit of 75 cents a share, according to Zachs. Zachs analysts predict that Viacom, Inc. (Nasdaq: VIAB) will report poor second quarter earnings with projections of a 3 percent drop in earnings from a year ago.Reuters estimates that Mastercard Inc (NYSE: MA) is expected to report first-quarter EPS of $6.18 on revenue of $1.93 billion, compared with a profit of $5.36 a share on revenue of $1.76 billion in the year-ago period. Finally, after the bell Wednesday, CBS Corporation (NYSE: CBS) and Visa Inc. (NYSE:V)report results. CBS is expected to report first-quarter earnings of 68 cents per share, compared with a profit of 54 cents a year ago, according to Reuters estimates. Wall Street is expecting higher profit for Visa as Zachs consensus estimate is calling for profit of about a dollar eighty per share.