Earnings Preview: UPS - Yahoo United Parcel Services (NYSE:UPS - News), the world's largest package delivery company, is slated to release its fourth quarter and fiscal 2011 earnings on January 31, before the opening bell. The current Zacks Consensus Estimates for the fourth quarter and fiscal 2011 are pegged at $1.26 and $4.25, respectively, representing substantial year-over-year increase of 16.23% and 19.25%. Looking at surprises, UPS posted an average positive surprise of 2.04% in the trailing four quarters. Hence, we will not be surprised if the carrier beats expectations in fourth quarter 2011, attributable to operating leverage with improved pricing and strong volume, yield improvement in the U.S. Domestic Package division andthe ramp in share buybacks.