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I'm going to begin by reviewing our financial results for the second quarter of 2012 and then I'll provide financial guidance for the third quarter. Unless otherwise noted, our discussion will be on a non-GAAP basis for all costs, gross margins, operating and net income, as well as EPS. And the primary difference between GAAP and non-GAAP financial information is noncash stock-based compensation. Please refer to the reconciliation of our financial information on a GAAP basis to that on a non-GAAP basis, which is included in the press release as published on our website.
For the quarter, the recurring revenues grew 24.3% to $64.6 million and represented 82% of total revenues. Total revenues grew by 23.3% to $79.2 million. Operating income increased by 55.4% to $10.3 million and the operating margin expanded to 13%. Net income grew to $5.9 million compared to $3.8 million last year, and the related net earnings per diluted share was $0.21 compared with $0.14 per diluted share in 2011.
Both the recurring revenue for the quarter of $64.6 million and the recurring revenue gross margin of 71.2% were slightly better than our forecast. Annualized customer retention exceeded 96% for our recurring revenue customer base. And please remember that our recurring revenue gross margin is impacted by the investment in and the continued growth of our Tax Filing business. Speaking of the Tax Filing business, our average daily float balance for the year-to-date was $300 million, and this is compared to $180 million for the same period last year. Due to the current yield environment, the revenue impact of these funds is immaterial. Service revenue was $14 million, representing an increase of 19.1% over the same quarter last year. The services gross margin for the quarter was slightly better than we expected. Keep in mind that on a sequential quarter basis, the revenues and gross margins reflect the seasonality of W-2 revenues. The gross margin rate for total revenues was 58.5% compared to 57.9% for the same period last year. The change from 2011 was related to the growth in recurring revenues and a 40-basis point expansion in the related gross margin. Operating expenses were $36 million for the quarter and were favorable to our expectations. We do expect a significant portion of these expenses to be incurred later this year and as reflected in our full year guidance.