New rate: The IRS will raise the national per-mile business driving rate to 40.5 cents per mile effective Jan. 1, up from 37.5 cents per mile -- an 8 percent jump that's the biggest one-year increase ever.

What it means: U.S. taxpayers can deduct 40.5 cents per mile in vehicle expenses for business miles driven next year.

Doing the math: AAA says the average driver puts on 15,000 miles per year. If they all were business miles, that would mean a deduction of $6,075.