US Bancorp ( USB) posted disappointing fourth-quarter results Tuesday morning. The Minneapolis-based bank earned 66 cents a share, up 5% year over year but a penny less than expectations; its $3.42 billion revenue number also missed the $3.45 billion consensus analyst estimate.Even so, the stock ended the session fractionally higher at $35.75, up 20 cents, as investors were attracted to US Bancorp's 4.5% dividend yield. The earnings report and subsequent reaction raise a couple of questions: Are the company's best earnings behind it, or can investors still cash in from buying the shares at current levels? I'll consider those questions as I try to answer the question: Should I do it? US Bancorp is the sixth-largest bank in the country, with $219 billion in assets and nearly 2,500 branches. This latest quarter marks the first earnings report for CEO Richard Davis, who ascended into the position last month after serving for two years as COO. He did not waste any time making a splash at his new position, either, as Davis boosted US Bancorp's quarterly dividend 21% his first day in office. The bank, which has increased its dividend 35 consecutive years, now pays out 40 cents a share, and its current 4.5% dividend yield is one of the highest in the banking sector. The company has delivered positive earnings growth eight of the past nine years, and the consensus analyst estimate is for another 8% growth in 2007, to $2.82 a share. While some banks' earnings have suffered because their balance sheets were not positioned for an inverted yield curve, US Bancorp derives 50% of its revenue from fee-based services.