The savings rate matters more than investment returns. The FIRE community has shown mathematically that a 50% savings rate compresses a typical 40-year career into roughly 17 years; a 75% savings rate to under 8 years, regardless of income level.
The denominator matters: net (after-tax) income is the standard. Counting employer pension contributions and matched 401(k) money is reasonable; counting paid-down mortgage principal is increasingly accepted because it builds equity.
Formel
Savings Rate = Savings ÷ Net Income
Beispiel
A household earning CHF 100k net and spending CHF 60k saves CHF 40k — a 40% savings rate, putting them on track to financial independence in about 22 years.