Stocks just did something they haven’t done in nearly three decades

New York (CNN) —& US markets wrapped up a blockbuster 2024 by marking an achievement so rare that it’s only ever happened a handful of times.Despite US stocks closing lower Tuesday in a disappointing December that saw the Dow drop over 2,000 points, or about 5%, and the S&P 500 slide 2.74%, this was a stellar year for stocks.The S&P 500& gained about 24% this year after rising 24% in 2023. The back-to-back gains of over 20% is the best performance for the benchmark index since 1997 and 1998, according to data from FactSet.It’s an extraordinary event for the modern-day version of the index. (Precursors also racked up that kind of performance three other times, in 1927 and 1928, 1935 and 1936 and in 1954 and 1955, according to a Bank of America analysis.)That means your retirement savings might be looking a little more cushioned than usual. Retirement plans in the form of a 401(k) or other pension fund are often invested in indices like the S&P 500. So, when stocks have a standout year, your account balance will benefit.Despite& fizzling out& in December and missing an expected “Santa Claus rally” to close out 2024, markets notched a blockbuster year,...