An Asian hedge-fund firm with a strong record has experienced a surprising loss from a small fund that made mistimed bets on stocks and currencies.

The fund managed by Danny Yong’s Singapore-based Dymon Asia Capital Ltd. had lost around 40% of its value in the year through August, following similar declines over the course of 2017, according to two people familiar with its performance. It has also seen redemptions which have reduced its assets under management to around $100 million.

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