The Internal Revenue Service's Ogden Service Center is gearing up for nearly 7 million federal tax returns expected to be filed as the April 17 deadline approaches, IRS spokesman Doug Green says.

As of Monday, the IRS center had received 5.5 million returns, about 8 percent ahead of predictions and 15 percent more than the same time last year, Green said.The center has issued more than 3 million refunds worth a total of $2.3 billion, he said. Refunds have averaged about $764, although the 325,000 electronically filed returns have averaged $1,241.

The error rate by taxpayers has been running about 10 percent, the same as last year, he said. About one-third of the errors were omissions of required entries, while 19 percent were math mistakes.

Green said the center received an average of 74,000 returns each day last week and expects an onslaught of about 2 million returns on April 18 and 19. This year the filing deadline is April 17, because April 15 falls on a Saturday.