US stocks substantially more expensive than global peers across all metrics

The S&P 500 is now more overvalued than ever, per this measure

S&P 500 price-to-sales ratio is well above its dot-com bubble peak

Wall Street strategists have been calling for fairly modest gains for U.S. stocks in 2020, with concerns over stock market valuations being commonly cited as a reason why investors should temper their expectations for equity returns in the coming quarters.