Stock ETFs Underperform on Average Gains January saw the Vanguard Total Stock Market Index Fund rise by 3.1%, trailing the average 3.35% gain in its category. Similarly, the Vanguard 500 Index Fund and SPDR S&P 500 ETF Trust both gained 2.78%, underperforming their category’s average. Global stocks fared better, climbing 3.25% overall.1