The Vanguard S&P 500 ETF (NYSEMKT: VOO) effectively mirrors the price action of the S&P 500 index for a minuscule annual expense ratio of 0.03%. Global supply chains remain challenged by the COVID-19 pandemic and Russia's invasion of Ukraine, and the U.S. inflation rate hit yet another four-decade high of 9.1% in June. If the S&P 500 were to, again, find a bottom at a multiple of 13 to 14 times Wall Street's forward-year earnings forecast, it would imply additional downside ranging from 11.9% to 18.2%, based on a forward P/E ratio of 15.9, as of July 13, 2022.