Net Asset Value And Financial Highlights (Tables)

9 Months Ended

Sep. 30, 2012

Schedule Of Net Asset Value Per Share

	Three Months Ended						Nine Months Ended
	September 30, 2012			September 30, 2011			September 30, 2012			September 30, 2011
Net Asset Value
Net asset value per Share, beginning of period	$	28.14		$	32.00		$	28.81		$	32.37
Net realized and change in unrealized gain (loss) on United States Treasury Obligations and Futures		1.41			(2.00	)		0.87			(2.22	)
Net investment income (loss)		(0.06	)		(0.07	)		(0.19	)		(0.22	)
Net income (loss)		1.35			(2.07	)		0.68			(2.44	)
Net asset value per Share, end of period	$	29.49		$	29.93		$	29.49		$	29.93
Market value per Share, beginning of period	$	28.22		$	31.74		$	28.88		$	32.35
Market value per Share, end of period	$	29.41		$	29.67		$	29.41		$	29.67
Ratio to average Net Assets*
Net investment income (loss)		(0.83	)%		(0.87	)%		(0.87	)%		(0.84	)%
Total expenses		0.91	%		0.91	%		0.93	%		0.92	%
Total Return, at net asset value **		4.80	%		(6.47	)%		2.36	%		(7.54	)%
Total Return, at market value **		4.22	%		(6.52	)%		1.84	%		(8.28	)%

* Percentages are annualized.

** Percentages are not annualized.