Investing $1,500 per month into the Vanguard S&P 500 ETF (VOO) is projected to reach a $1 million valuation by 2046. While the asset has shown historical growth of 556% to a price of $672.12, the author suggests that relying solely on VOO may result in lower relative wealth compared to others by that timeframe. The data highlights a rapid increase in the U.S. millionaire population, which is expected to reach 26 million by 2026.