I spend much much less what I make (maximum 35%). So every month I save at least 2 more months of living. Over the past 3 years doing it regularly I have enough saved for some 10 years.
Most of my money is invested in things that pays 2/3x inflation and are quite safe investments. Also I'm not planning on starting taking the money out yet so probably will get to 20 or more years of expenses. Then, just the profits of the money would be enough to pay my expenses.