[Excel_Wizard]

The chart shown at macrotrends does not show total return (dividends included and reinvested). The investor would have broken even much earlier. January 1929 to January 1960 shows ~25% real return without dividends reinvested and ~499% real return with dividends reinvested.

https://dqydj.com/dow-jones-return-calculator/

[refurb]

Exactly this. You can't ignore dividends.

Based on this [1] calculator, you'd break event by 1940.

[1]https://dqydj.com/dow-jones-return-calculator/

[perl4ever]

Yes, but on the other hand, traditionally the point of dividends is that you don't reinvest them. You should still include them in returns though. But it seems unrealistic for anyone without perfect knowledge of the future to have reinvested every penny over 30 years including the depression, WWII, and the earliest, most paranoid part of the cold war and nuclear age.