Bill Ackman's fund bounced back last week but still had a lousy August

August was a month to forget for Bill Ackman.

Pershing Square Holdings had been up 10.1% through the end of July.

Then the market crashed and the fund went down with it, dropping 13.1% from August 1 to August 25. That put the fund in the red for the year, down 4.3%.

It appears that Ackman was able to pare back some of those losses in the last few days of the month.

Pershing Square Holdings finished the month down 9.2%, leaving the fund down 0.1% for the year, according to an investor update.

Ackman holds large positions in a handful of publicly traded companies. In an investor update, he said Pershing wouldn't be forced to sell out of those stocks.

Ackman wrote that all gains for the year had been erased because of "significant volatility in the investment markets over the past few weeks, largely driven by the decline of the Chinese stock markets, and the fear that slowing growth in China will have repercussions for businesses around the world."

August was a challenging month for many investors. The average hedge fund was down 2.2%, according to data from Hedge Fund Research. During that time, the S&P 500 fell 6.2%. Meanwhile, the average hedge fund is down 1% for the year, while the S&P 500 is down about 6.2% year-to-date.