MSCI's All Country World Index, which tracks stocks across 49 countries, was down 0.14% after the start of European trading, off Friday's record high. The gauge's price-to-earnings ratio is at its highest level since early 2010.
Morgan Stanley noted that despite the S&P 500 making all-time highs, small-cap stocks represented by the Russell 2000 small-cap index have underperformed the S&P 500 by 8% since peaking on March 12.