our consolidated financial statements and the related notes included in Part II, Item 8, "Financial Statements and Supplementary Data" of this Annual Report on Form 10-K. In addition to our historical consolidated financial information, the following discussion contains forward-looking statements that reflect our plans, estimates, and beliefs. Our actual results could differ materially from those discussed in the forward-looking statements. Factors that could cause or contribute to these differences include those discussed below and elsewhere in this Annual Report on Form 10-K, particularly in Part I, Item 1A, "Risk Factors." For a discussion of limitations in the measurement of certain of our user metrics, see the section entitled "Limitations of Key Metrics." about. personalized and social. location, gender, or interests. We offer marketers a unique combination of reach, relevance, social context, and engagement to enhance the value of their ads. ended December 31, 2012, we recorded revenue of $5.09 billion, income from operations of $538 million and net income of $53 million. Total costs and expenses increased 133% compared to revenue growth of 37% due to significant increases in share-based compensation and related payroll tax expenses for restricted stock units (RSUs) and increases in headcount for the year ended December 31, 2012. During fiscal 2012, we recognized $1.72 billion of share-based compensation and related payroll tax expenses. Of these amounts, $1.13 billion was due to the recognition of share-based compensation and related payroll tax expenses related to RSUs granted prior to January 1, 2011 (Pre-2011 RSUs) triggered by the completion of our initial public offering (IPO) in May 2012. Our effective tax rate for the year ended December 31, 2012 has exceeded the U.S. statutory rate primarily due to the impact of non-deductible share-based compensation and losses arising outside the United States in jurisdictions where we do not receive a tax benefit. |