Two useful metrics to test the valuation of domestic equity markets — Tobin’s Q and the cyclically-adjusted S&P 500 price-to-earnings ratio — continue to show equity markets may be slightly overvalued. That said, these two metrics, though robust, are inherently backward-looking. With the U.S. economy experiencing the strongest sustained period of growth in the current business cycle current, future valuations could very well continue to melt up due to improved growth expectations.