Hedge funds are the most bullish on silver in seven months and investors’ holdings are expanding toward a record on speculation the metal will outperform gold as central banks seek to boost growth.

Wagers on rising prices jumped 10-fold since June, U.S. Commodity Futures Trading Commission data show. Investors bought 717.2 metric tons valued at $790 million through exchange-traded products this quarter, the most in a year, according to data compiled by Bloomberg. Prices will increase for at least the next three quarters and average $38 an ounce in the three months through June, or 11 percent more than now, based on the median of 14 analyst estimates compiled by Bloomberg.