Actual results may materially differ from anticipated results described or implied in these forward-looking statements. Please refer to the Risk Factors section of the annual report on Form 10-K for the year ended December 31, 2011, for additional factors that could materially affect the company's financial performance. The company undertakes no obligation to publicly update any forward-looking statements whether as a result of new information, future events or otherwise.
At this time, I'd like to introduce Greg Henslee.
Gregory L. Henslee
Thanks, Tom. Good morning, everyone, and welcome to the O'Reilly Auto Parts second quarter conference call. Participating on the call with me this morning is, of course, Tom McFall, our Chief Financial Officer; and Ted Wise, our Chief Operating Officer. David O'Reilly, our Executive Chairman, is also present.
First, I'd like to congratulate Team O'Reilly for our continuing success in providing the highest levels of customer service in our industry. Despite the pull-forward of a portion of the spring business into the first quarter, along with the difficult consumer spending environment, we were able to achieve a respectable 2.5% comparable store sales increase and generated 20% increase in earnings per share. This marks our 14th straight quarter of increasing adjusted earnings per share in excess of 15%.
Each and every one of us plays an important role in our company's success. Whether your role is in one of our distribution centers, stores, outside sales or here at our headquarters, your contribution is important in ensuring our customer service levels exceed our competitors' and that we operate as productively as possible. Thanks to all of you for your hard work in the second quarter and for the commendable results.
Now on to some details about our quarterly performance. As most of you know, our original comparable store sales guidance for the second quarter was 3% to 5%. And when it became clear that we wouldn't achieve the bottom end of that range, we updated our guidance. Based on these softer-than-expected results, I'll go into a little more detail than we typically disclose concerning the progression and composition of our quarterly comparable store sales increase and give some color on our rationale for the third quarter comparable store sales guidance.