The U.S. stock market and gold are nearing peak valuation levels, according to Mark Hulbert’s analysis of four investor-sentiment indexes. - Getty Images The U.S. stock market appears to be expensive by a commonly used measure. The S&P 500’s forward price-to-earnings multiple is 22.5, which is 20% higher than its 10-year average forward P/E of 18.8, according to LSEG. Then again, the S&P 500 SPX is highly concentrated to the largest technology companies, which have been growing rapidly. So maybe during t ...