I agree with this directionally, however I think you'll make more like 7.2% per year, and inflation will be about 2.5% per year. You'll also likely pay about 30% in federal and local taxes in the USA on it since you're actually selling it to live on it (more on taxes later). So you'll pay 2.2% in taxes. So on average you'll get 7.2 - (2.5 + 2.2) = 2.5% of income. If you have $10M, you can withdraw about 250K a year in today's dollars every year. i.e next year you can withdraw 256.3K or so, and keep doing this to keep your current standard of living. In down years you may want to adjust / tighten belt a tiny bit to not veer off track too much. And you can get cute with taxes but not recommended. That loan interest will add up over time, and when it's time to actually pay those loans, you'll still sell stock and pay taxes on it, unless your offspring inherit both.. and who knows what the laws will be then.
The 7.2% number is already adjusted for inflation. Historically the stock market has gotten about 10% nominal return, 6.5-7% real.
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