Employee Retirement Plans

6 Months Ended

Jun. 30, 2011

Employee Retirement Plans [Abstract]

Employee Retirement Plans

11. Employee Retirement Plans

The components of net pension and postretirement benefits costs are summarized in the following table:

	Three Months						Six Months
	ended June 30,						ended June 30,
(millions)	2011			2010			2011			2010
Pension:
Service cost of benefits earned	$	7		$	6		$	14		$	13
Interest cost on projected benefit obligation		16			16			32			32
Expected return on plan assets		(17	)		(16	)		(33	)		(33	)
Net amortization		7			4			13			8
Net pension cost	$	13		$	9		$	26		$	20
Postretirement:
Service cost of benefits earned	$	1		$	2		$	3		$	4
Interest cost on projected benefit obligation		3			5			7			9
Net amortization		(5	)		(5	)		(11	)		(9	)
Net postretirement cost	$	(1	)	$	2		$	(1	)	$	4

     During the second quarter of 2011, we made a contribution to the USG Corporation Retirement Plan Trust, or Trust, that was recorded on the condensed consolidated balance sheet at $30.9 million. This contribution consisted of 2,084,781 shares of our common stock, or the Contributed Shares, and was recorded on the condensed consolidated balance sheet at the June 20, 2011 closing price of $14.84 per share. The Contributed Shares are not reflected on the condensed consolidated statement of cash flows because they were treated as a noncash financing activity. The Contributed Shares were valued for purposes of crediting the contribution to the Trust at a discounted value of $14.39 per share ($14.84 less a 3% discount), or approximately $30.0 million in the aggregate, by an independent appraiser retained by Evercore Trust Company, N.A., or Evercore, an independent fiduciary that has been appointed as investment manager with respect to the Contributed Shares. The Contributed Shares are registered for resale, and Evercore has authority to sell some or all of them, as well as other of our shares in the Trust, in its discretion as fiduciary.

     During the first quarter of 2011, we contributed $10 million in cash to our pension plan in Canada. In July 2011, we contributed $10 million in cash to the Trust.