cloud computing and emerging markets. There are many factors that make it difficult for us to predict future revenue trends for our business, including those discussed in Part I, Item 1A entitled “Risk Factors” in this Form 10-K. Revenue for fiscal 2012 was $427.7 million, which represented a decrease of 4.0% from the record $445.4 million reported for fiscal 2011. The decrease in revenue from fiscal 2011 was primarily due to the soft industry conditions during the first half of the fiscal year. In spite of the challenging industry and macroeconomic conditions, we were able to grow both our polishing pads business and our ESF business. We also increased our revenue in South Korea by approximately 22% from fiscal 2011. South Korea has been an area of strategic emphasis for the Company since it represents the second largest CMP consumables market in the world. Gross profit expressed as a percentage of revenue for fiscal 2012 was 47.7%, which represents a decrease from the 48.1% reported for fiscal 2011, but was near the upper end of our full year guidance range of 46% to 48% of revenue. The decrease in gross profit percentage from fiscal 2011 was primarily due to higher fixed manufacturing costs, pricing impacts, and lower sales and production volumes, partially offset by lower variable manufacturing costs and higher manufacturing yields. We expect our gross profit for full fiscal year 2013 to continue to be in the range of 46% to 48% of revenue. However, we may experience fluctuations in our gross profit due to a number of factors, including the extent to which we utilize our manufacturing capacity and changes in our product mix, which may cause our quarterly gross profit to be above or below this range. Operating expenses of $137.5 million, which include research, development and technical, selling and marketing, and general and administrative expenses, increased 2.8%, or $3.8 million, from the $133.7 million reported for fiscal 2011. The increase was primarily due to bad debt expense related to a customer bankruptcy that we reported in the second quarter of fiscal 2012, costs associated with our leveraged recapitalization with a special cash dividend, and higher expenses for research and development materials. These increases were partially offset by lower staffing-related costs. In fiscal 2013, we expect our full year operating expenses to be in the range of $132 million to $136 million. Diluted earnings per share of $1.75 in fiscal 2012 decreased 20.4%, or $0.45, from the record $2.20 reported in fiscal 2011. The decrease was primarily due to decreased sales volume, a lower gross profit percentage, higher operating expenses noted above, and interest expense on our Term Loan. Diluted earnings per share in fiscal 2012 included $0.20 in adverse items including the bad debt expense related to a customer bankruptcy and costs associated with our leveraged recapitalization with a special cash dividend, as well as $0.06 for interest expense on our Term Loan. Critical Accounting Policies and Estimates This MD&A, as well as disclosures included elsewhere in this Form 10-K, are based upon our audited consolidated financial statements, which have been prepared in accordance with accounting principles generally accepted in the United States. The preparation of these financial statements requires us to make estimates and judgments that affect the reported amounts of assets, liabilities, revenues and expenses, and related disclosure of contingencies. On an ongoing basis, we evaluate the estimates used, including those related to bad debt expense, warranty obligations, inventory valuation, valuation and classification of auction rate securities, impairment of long-lived assets and investments, business combinations, goodwill, other intangible assets, sharebased compensation, income taxes and contingencies. We base our estimates on historical experience, current conditions and on various other assumptions that we believe to be reasonable under the circumstances, the results of which form the basis for making judgments about the carrying values of assets and liabilities that are not readily apparent from other sources, as well as for identifying and assessing our accounting treatment with respect to commitments and contingencies. Actual results may differ from these estimates under different assumptions or conditions. We believe the following critical accounting policies involve significant judgments and estimates used in the preparation of our consolidated financial statements. Allowance for Doubtful Accounts We maintain an allowance for doubtful accounts for estimated losses resulting from the potential inability of our customers to make required payments. Our allowance for doubtful accounts is based on historical collection experience, adjusted for any specific known conditions or circumstances. While historical experience may provide a reasonable estimate of uncollectible accounts, actual results may differ from what was recorded. In fiscal 2012, we recorded $3.7 million in bad debt expense for Elpida Memory, Inc. (Elpida), a significant customer in Japan that filed for bankruptcy protection in February 2012. We will continue to monitor the financial solvency of all of our customers and, if global economic conditions worsen, we may have to record additional increases to our allowance for doubtful accounts. As of September 30, 2012, our allowance for doubtful accounts represented 8.2% of gross accounts receivable. If we had increased our estimate of bad debts to 9.2% of gross accounts receivable, our general and administrative expenses would have increased by $0.6 million. 22