Stocks are up 18.7% year-to-date, which is good news for portfolios and 401(k)s, but did you know that most of the heavy lifting has been done by a very small number of S&P 500 stocks? You may be surprised to learn that more than 80% of gains so far in 2023 are due to the [...] The post The Concentration Risk Lurking In Your 401(K) appeared first on ETF Trends .