Investors’ desire for precious metals is deepening after Mario Draghi’s $1.2 trillion pledge drove gold to a five-month high and silver to the brink of a bull market.

Their buying helped boost the value of exchange-traded products backed by gold and silver by $8.2 billion this month, the most since September 2012, data compiled by Bloomberg show. Hedge funds and other speculators in futures and options are the most bullish on gold in two years and have bet more on silver in all but two weeks since the start of November.