The price-to-earnings ratio of the index, the high-level gauge of a stock or market's relative value, crossed its rolling three-year average in early 2013 and got close to the break point during the market struggles in the first quarter of 2016. Since those recent lows, market P/Es have ascended to new highs, reaching 21.7 as of Tuesday's close, raising questions about whether the fundamentals and earnings are there.
Earnings have recovered in 2017 after declining in 2015 and into 2016, spending much of 2016 under their rolling three-year averages before surfacing earlier this year.
