v3.8.0.1

Statements of Financial Condition (Parenthetical) - USD ($)	Sep. 30, 2017	Dec. 31, 2016
Short-term U.S. government and agency obligations, cost	$ 3,181,464,501	$ 3,038,837,465
ProShares VIX Short-Term Futures ETF [Member]
Short-term U.S. government and agency obligations, cost	186,708,857	147,990,045
ProShares VIX Mid-Term Futures ETF [Member]
Short-term U.S. government and agency obligations, cost	35,953,365	45,486,489
ProShares Short VIX Short-Term Futures ETF [Member]
Short-term U.S. government and agency obligations, cost	770,073,989	170,391,741
ProShares Ultra VIX Short-Term Futures ETF [Member]
Short-term U.S. government and agency obligations, cost	521,285,333	434,676,067
ProShares UltraShort Bloomberg Crude Oil [Member]
Short-term U.S. government and agency obligations, cost	246,653,071	205,694,828
ProShares UltraShort Bloomberg Natural Gas [Member]
Short-term U.S. government and agency obligations, cost	2,998,485	2,899,188
ProShares UltraShort Gold [Member]
Short-term U.S. government and agency obligations, cost	34,939,314	60,540,275
ProShares UltraShort Silver [Member]
Short-term U.S. government and agency obligations, cost	17,965,709	21,549,766
ProShares Short Euro [Member]
Short-term U.S. government and agency obligations, cost	5,998,008	13,164,807
ProShares UltraShort Australian Dollar [Member]
Short-term U.S. government and agency obligations, cost	7,997,344	12,909,895
ProShares UltraShort Euro [Member]
Short-term U.S. government and agency obligations, cost	219,674,153	337,373,566
ProShares UltraShort Yen [Member]
Short-term U.S. government and agency obligations, cost	137,812,663	257,103,135
ProShares Ultra Bloomberg Crude Oil [Member]
Short-term U.S. government and agency obligations, cost	562,320,399	885,046,303
ProShares Ultra Bloomberg Natural Gas [Member]
Short-term U.S. government and agency obligations, cost	42,918,384	36,183,384
ProShares Ultra Gold [Member]
Short-term U.S. government and agency obligations, cost	101,893,747	95,356,703
ProShares Ultra Silver [Member]
Short-term U.S. government and agency obligations, cost	270,613,725	295,296,440
ProShares Ultra Euro [Member]
Short-term U.S. government and agency obligations, cost	10,995,458	11,891,729
ProShares Ultra Yen [Member]
Short-term U.S. government and agency obligations, cost	$ 4,662,497	$ 5,283,104

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