The Dow Jones Industrial Average is a garbage index with components selected arbitrarily. No one in finance takes it seriously.
No one can guarantee stock market returns, but over decades it's a lot safer than depending on pension contributions from a single company. And most 401(k) plans now offer target date mutual funds which automatically reduce stock exposure over time, thus reducing risk of capital loss as you approach retirement.
I used the DJIA because Nasdaq 100 and S&P500 aren’t even 100 years old yet, so I can’t go back to 1929 or even 1945 and see how the S&P500 was doing. Dow was the only index back then that still exists today as far as I’m aware.
The modern US financial system has only really existed since 1971 so I fail to see the point of looking back further for retirement planning. And the DJIA is constructed in such a way that comparisons going back that far are nearly meaningless. You're just looking at noise.
Even worse. If you’re using a TRD fund to stash your retirement, it will severely underperform in a bull market, and if it spares you somewhat from a bear market, well… you probably weren’t going to be able to retire on that money anyway. Then there’s the relatively high expense ratio most of those “actively managed” funds have.
No one can guarantee stock market returns, but over decades it's a lot safer than depending on pension contributions from a single company. And most 401(k) plans now offer target date mutual funds which automatically reduce stock exposure over time, thus reducing risk of capital loss as you approach retirement.