I made 2 videos the other days comparing the historical returns of these 4 ETFs: IVV, VOO, SPY and VTI. In the first video, I found that a VOO had the best historical returns in a randomly chose investment time span. In the second video, I found that VOO was still the best accounting for their return standard deviation, or risk, or fluctuation, when I divided their returns by the return standard deviation. Why might VOO be better than SPY, IVV and VTI? Out of curiosity, I went digging for information. Some of the known facts that would not make VOO the best: VTI contains mid-, and small-cap equity, while the others don't. SPY has the highest expense ratio of 0.09%, while the others are 0.03%. Then I found the possible reason, their turnover rate: SPY: 2% VOO: 2% IVV: 3% VTI: 3.4% With this and the fact that SPY has the highest expense ratio, VOO might just be the best ETF among :