SALEM — The state soon will begin mailing 1.6 million rebate checks, sending more than $1 billion back to Oregon taxpayers.

SALEM — The state soon will begin mailing 1.6 million rebate checks, sending more than $1 billion back to Oregon taxpayers.

The exact date of the mailing is a secret for security reasons, said Rosemary Hardin, spokeswoman for the Oregon Department of Revenue.

The state's printing plant began producing the checks this week.

The "kicker" checks go to taxpayers when income tax proceeds to the state treasury exceed estimates by more than 2 percent.

This year, taxpayers will get back about a fifth of their 2006 state income tax, the Department of Revenue said.

A typical check will be $200 to $500, but the amounts vary widely, based on income. One in 12 taxpayers won't get any money. At the upper end, 167 taxpayers will get back more than $100,000 apiece.

The Department of Revenue says taxpayers can calculate their kicker rebates by multiplying 0.186 times the tax figure on various forms: Line 29 on Form 40, Line 13 on Form 40S, Line 51 on Form 40N, and Line 50 on Form 40P.

— The Associated Press