NOTE 4. INCOME TAXES

On a quarterly basis, we estimate what our effective tax rate will be for the full fiscal year and record a quarterly income tax provision based on the anticipated rate. As the year progresses, we refine our estimate based on the facts and circumstances, including discrete events, by each tax jurisdiction. Our effective tax rate for the three months ended March 31, 2015 was 35%, compared with 37% for the three months ended March 31, 2014.

The differences between federal income taxes computed at the federal statutory rate and reported income taxes for the three months ended March 31, 2015 and 2014 are as follows:

	Three Months Ended
	March 31
	2015			2014
Statutory federal tax provision (benefit)	$	(82,000	)	$	51,000
State income taxes (benefits)	(10,000		)	7,000
Income tax credits	(13,000		)	(8,000		)
Other	1,000			—
Income tax expense (benefit)	$	(104,000	)	$	50,000

At March 31, 2015, we had $54,000 of net uncertain tax benefit positions remaining in other long-term liabilities related to research and development credits that would increase our effective income tax rate if recognized. At December 31, 2014, we had $56,000 of net uncertain tax benefit positions recorded in other long-term liabilities that would reduce our effective income tax rate if recognized.