Gold mining stocks

Gold has been in the headlines lately as it climbs to new highs, prompting many investors to look for ways to benefit from the rally. However, many institutional investors – such as mutual funds and pension funds – face restrictions on buying physical gold or gold-backed ETFs. Instead, they often turn to gold mining stocks to gain indirect exposure to gold’s price. That approach seems logical on the surface: mining stocks typically offer leveraged exposure to gold’s movements. But as highlighted by Dirk G. Baur, Allan Trench, and Lichoo Tay in their recent study “Gold Shares Underperform Gold Bullion”, this strategy can be misleading. The authors demonstrate that, over the long run, gold mining shares structurally underperform physical gold itself.

Can we truly rely on the opening price in OHLC data for backtesting? While the overnight drift effect is well-documented in equities, we investigated its presence in gold using the GLD ETF and then extended our analysis to the GDX – Gold Miners ETF, where we observed an unusually strong overnight return exceeding 30% annualized. However, when we tested execution at 9:31 AM using 1-minute data, the anomaly diminished significantly, suggesting that the extreme return was partially a data artifact. This finding highlights the risks of blindly trusting OHLC open prices and underscores the need for higher-frequency data to validate execution assumptions.