Hedge funds have had a difficult year. Stock market volatility (especially the S&P 500) has squashed gains for most “smart money” funds, except for those holding Bitcoin.

According to Hedge Fund Research Index (HFRI), hedge funds this year returned a paltry 3.5 percent, while the S&P doubled that number. Further, the HFRI Composite Index added just half a percent in May, though the market added a whole percent. After eight years of bull market and strong gains in the S&P, hedge funds continue to underperform compared to indexed funds.

However, according to analysts, two strategies outperformed the indexed market funds. The first was high exposure to technology firms like Apple and Facebook where gains through the spring have been strong.

Second, the strongest returns were among the HFRI Macro: Currency Index which is holding Bitcoin. Other currencies did well but Bitcoin outperformed them all. The substantial gains of Bitcoin that made headlines through the spring have produced enormous returns for individual Bitcoin holders, as well as for the currency funds.

Bitcoin hit a record high in May and has now touched another high this week, driving returns for the hedge funds that took risks on the cryptocurrency last year.