Exchange-traded funds have enjoyed healthy investment returns this year, some comfortably outpacing the S&P 500 and other major indexes that have hit all-time highs.

Investors have flocked to ETFs, which try to mimic the performance of a single sector or index, for their low fees, liquidity, and tax efficiency.

Today’s bull market is propped up by the funds, which have contributed $300 billion to equities this year, Goldman Sachs reports. Moody’s Investor Service estimates that ETFs will make up half of the US stock market in less than 10 years.

We’ve compiled a list of the best-performing ETFs with more than $100 million in assets, ranked by 2017 year-to-date performance, using Bloomberg data. The ETFs on our list have delivered well over 60% in returns, while the S&P 500 is up by 13.12%.

The world of ETFs is vast, and choosing the right one can be complicated. Some of the ETFs with the highest returns are 3X levered, making them pretty risky, but they are still attractive for their returns.

Scroll down to find out more about these funds, listed from lowest to highest in performance.

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VanEck Vectors Rare Earth/Strategic Metals ETF (REMX)

Foto: source Markets Insider

Assets: $141.87 million

2017 Return: 60.02%

2017 investments in the fund: $69.11 million

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Data provided by Bloomberg


Guggenheim Invest China Technology ETF (CQQQ)

Foto: source Markets Insider

Assets: $317.08 million

2017 Return: 64%

2017 investments in the fund: $219.26 million

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Data provided by Bloomberg


Direxion Daily Healthcare Bull 3X Shares (CURE)

Foto: source Markets Insider

Assets: $151.40 million

2017 Return: 66.27%

2017 investments in the fund: -$103.01 million

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Data provided by Bloomberg


ProShares UltraPro Dow30 (UDOW)

Foto: source Markets Insider

Assets: $299.30 million

2017 Return: 68.32%

2017 investments in the fund: 5.95 million

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Data provided by Bloomberg


ARK Web X.0 ETF (ARKW)

Foto: source Markets Insider

Assets: $114.72 million

2017 Return: 69.44%

2017 investments in the fund: $75.5 million

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Data provided by Bloomberg


ARK Innovation ETF (ARKK)

Foto: source Markets Insider

Assets: $152.27 million

2017 Return: 73.82%

2017 investments in the fund: $152.27 million

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Data provided by Bloomberg


ProShares Ultra Technology (ROM)

Foto: source Markets Insider

Assets: $264.46 million

2017 Return: 76.14%

2017 investments in the fund: $42.10 million

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Data provided by Bloomberg


Direxion Daily MSCI India Bull 3X Shares (INDL)

Foto: source Markets Insider

Assets: $108.68 million

2017 Return: 109.73%

2017 investments in the fund: -$28.91 million

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Data provided by Bloomberg


Direxion Daily Technology Bull 3X Shares (TECL)

Foto: source Markets Insider

Assets: $437.74 million

2017 Return: 110.97%

2017 investments in the fund: $38.95 million

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Data provided by Bloomberg


Direxion Daily MSCI Emerging Market Bull 3X Shares (EDC)

Foto: source Markets Insider

Assets: $279.33 million

2017 Return: 117.66%

2017 investments in the fund: -$19.80 million

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Data provided by Bloomberg


Direxion Daily FTSE China Bull 3X Shares (YINN)

Foto: source Markets Insider

Assets: $247.48 million

2017 Return: 125.97%

2017 investments in the fund: -$16.05 million

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Data provided by Bloomberg


Direxion Daily S&P Biotech Bull 3X Shares (LABU)

Foto: source Markets Insider

Assets: $378.34 million

2017 Return: 146.15%

2017 investments in the fund: -$220.83 million

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Data provided by Bloomberg


Direxion Daily Semiconductor Bull 3X Shares (SOXL)

Foto: source Markets Insider

Assets: $510.04 million

2017 Return: 151.07%

2017 investments in the fund: $93.70 million

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Data provided by Bloomberg


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