With the start of the first-quarter earnings season, U.S. stock-market investors are waiting to see whether the results point to a business environment that is thriving and supportive of the market’s rally over the past several years, or whether the move has been overdone. Turns out, both bulls and bears have data they can marshal in their favor. According to data from FTSE Russell and Thomson Reuters, the U.S. stock market was recently trading at its most expensive levels since the dot-com era, and — even after the first correction for the Dow Jones Industrial Average DJIA, +0.87% and the S&P 500 SPX, +0.81% in about two years — it continues to trade one standard deviation above a historical range. The data is based on the forward price-to-earnings ratio for stocks, which is currently above 17, compared with the long-term average of about 15. This measure of valuation can be seen mapped out in the following chart. The recent peak of the forward P/E represented a nearly 20-year high, per FTSE Russell. via