Statements of Financial Condition (Unaudited) - USD ($)		Mar. 31, 2016	Dec. 31, 2015
Assets
United States Treasury Obligations, at fair value (cost $768,709,369 and $1,077,885,299, respectively)	[1]	$ 768,801,792	$ 1,077,913,905
Cash held by custodian		52,655,471	51,943,740
Variation margin receivable			4,489,462
Total assets		821,457,263	1,134,347,107
Liabilities
Variation margin payable		2,086,578
Management fee payable		526,271	728,477
Brokerage fee payable		3,941	3,814
Total liabilities		$ 2,616,790	$ 732,291
Commitments and Contingencies (Note 9)
Equity
Shareholder's equity—General Shares		$ 981	$ 1,026
Shareholders' equity—Shares		818,839,492	1,133,613,790
Total shareholders' equity		818,840,473	1,133,614,816
Total liabilities and equity		$ 821,457,263	$ 1,134,347,107
General Shares outstanding		40	40
Shares outstanding		33,400,000	44,200,000
Net asset value per share		$ 24.52	$ 25.65
Market value per share		$ 24.53	$ 25.64

[1] $32,903,175 and $34,998,099, respectively is restricted for maintenance margin purposes.