Peter Oppenheimer, the chief global equities strategist at Goldman Sachs, has added to a growing chorus of views urging investors to switch from U.S. equities to European.

U.S. indexes like the S&P 500 outperformed other global bourses last year and have continued to hit record highs in 2015. However, Oppenheimer argues that the gains are now coming at a slower rate than their European counterparts.