BullionVault, an online service for investors to buy and sell physical gold and silver, said its Gold Investor Index fell in December to an almost five-year low.

The gauge, which measures the balance of buyers against sellers, slipped to 50.5 from 52.1 in November, the London-based company said in an e-mailed report today. That’s the lowest level since February 2010 and marked the biggest drop since 2013. A reading above 50 indicates more buyers than sellers.