(14)Income Taxes

An analysis of the difference between the statutory and effective tax rates for the three months ended March 31, 2015 and 2014 follows:

	Three months ended March 31,
	2015		2014
U.S. federal statutory tax rate	35.0	%	35.0	%
Tax credits	(2.4	)	(1.6	)
Tax exempt interest income	(1.4	)	(1.7	)
Cash surrender value of life insurance	(1.0	)	(2.0	)
State income taxes	0.9		1.0
Other, net	0.4		0.1
Effective tax rate	31.5	%	30.8	%

US GAAP provides guidance on financial statement recognition and measurement of tax positions taken, or expected to be taken, in tax returns. As of March 31, 2015 and December 31, 2014, the gross amount of unrecognized tax benefits, including penalties and interest, was $45 thousand and $42 thousand, respectively. If recognized, the tax benefits would reduce tax expense and accordingly, increase net income. The amount of unrecognized tax benefits may increase or decrease in the future for various reasons including adding amounts for current tax year positions, expiration of open income tax returns due to statutes of limitation, changes in management’s judgment about the level of uncertainty, status of examination, litigation and legislative activity and the addition or elimination of uncertain tax positions.

Federal and state income tax returns are subject to examination for the years after 2011.