Best response here. Of critical importance -- percent of your income that you spend is the most relevant variable. Over simplified, but if you can survive on

Best response here. Of critical importance -- percent of your income that you spend is the most relevant variable. Over simplified, but if you can survive on 5% of your income, it won't take you long to be able to sustain that standard of living indefinitely (assuming you're able to save / invest the majority of the remainder).