7.	Income Taxes

Income tax benefit/expense reported in the Corporation's consolidated statements of earnings includes income tax benefit/expense on earnings attributable to both the Corporation and its noncontrolling interests.


	Six Months Ended June 30,
	2011			2010
Estimated effective income tax rate:
Continuing operations		26.9	%		29.4	%

Discontinued operations		26.2	%		28.3	%

Consolidated overall		26.9	%		29.4	%

The Corporation's effective income tax rate reflects the effect of federal and state income taxes and the impact of differences in book and tax accounting arising from the net permanent benefits associated with the depletion allowances for mineral reserves and the domestic production deduction. The effective income tax rates for discontinued operations reflect the tax effects of individual operations' transactions and are not indicative of the Corporation's overall effective income tax rate.

The consolidated overall estimated effective income tax rate for the six months ended June 30, 2011 included the following discrete events: resolution of a federal tax and interest overpayment of $1,730,000 related to the 2006 tax year and an agreed-upon refund of $1,060,000 for the double taxation of the Corporation's wholly-owned Canadian subsidiary for the 2001 and 2002 tax years.

The change in the year-to-date consolidated overall estimated effective income tax rate during the second quarter of 2010, when compared with the year-to-date consolidated overall estimated effective income tax rate as of March 31, 2010, decreased consolidated net earnings for the six months ended June 30, 2010 by $5,436,000, or $0.12 per diluted share.