v3.8.0.1

Statements of Changes in Shareholders' Equity (Parenthetical)	9 Months Ended
	Sep. 30, 2017 shares
Addition, shares	196,810,016
Redemption, shares	168,876,807
Net addition (redemption), shares	27,933,209
ProShares VIX Short-Term Futures ETF [Member]
Addition, shares	6,125,000
Redemption, shares	2,301,046
Net addition (redemption), shares	3,823,954
ProShares VIX Mid-Term Futures ETF [Member]
Addition, shares	850,000
Redemption, shares	150,000
Net addition (redemption), shares	700,000
ProShares Short VIX Short-Term Futures ETF [Member]
Addition, shares	46,750,000
Redemption, shares	40,650,000
Net addition (redemption), shares	6,100,000
ProShares Ultra VIX Short-Term Futures ETF [Member]
Addition, shares	51,185,000
Redemption, shares	28,223,145
Net addition (redemption), shares	22,961,855
ProShares UltraShort Bloomberg Crude Oil [Member]
Addition, shares	10,700,000
Redemption, shares	9,950,000
Net addition (redemption), shares	750,000
Pro Shares UltraPro 3X Short Crude Oil ETF [Member]
Addition, shares	1,050,008
Redemption, shares	150,000
Net addition (redemption), shares	900,008
ProShares UltraShort Bloomberg Natural Gas [Member]
Addition, shares	300,000
Redemption, shares	300,000
Net addition (redemption), shares	0
ProShares UltraShort Gold [Member]
Addition, shares	300,000
Redemption, shares	500,000
Net addition (redemption), shares	(200,000)
ProShares UltraShort Silver [Member]
Addition, shares	700,000
Redemption, shares	600,000
Net addition (redemption), shares	100,000
ProShares Short Euro [Member]
Redemption, shares	150,000
Net addition (redemption), shares	(150,000)
ProShares UltraShort Australian Dollar [Member]
Redemption, shares	100,000
Net addition (redemption), shares	(100,000)
ProShares UltraShort Euro [Member]
Addition, shares	1,800,000
Redemption, shares	4,250,000
Net addition (redemption), shares	(2,450,000)
ProShares UltraShort Yen [Member]
Addition, shares	900,000
Redemption, shares	2,350,000
Net addition (redemption), shares	(1,450,000)
ProShares Ultra Bloomberg Crude Oil [Member]
Addition, shares	65,600,000
Redemption, shares	70,852,616
Net addition (redemption), shares	(5,252,616)
ProShares UltraPro 3x Crude Oil ETF [Member]
Addition, shares	1,400,008
Redemption, shares	1,100,000
Net addition (redemption), shares	300,008
ProShares Ultra Bloomberg Natural Gas [Member]
Addition, shares	6,600,000
Redemption, shares	3,050,000
Net addition (redemption), shares	3,550,000
ProShares Ultra Gold [Member]
Addition, shares	400,000
Redemption, shares	950,000
Net addition (redemption), shares	(550,000)
ProShares Ultra Silver [Member]
Addition, shares	950,000
Redemption, shares	2,000,000
Net addition (redemption), shares	(1,050,000)
ProShares Ultra Euro [Member]
Addition, shares	1,200,000
Redemption, shares	1,250,000
Net addition (redemption), shares	(50,000)

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