My actual comfort zone is 0%. I "retired" from my career job of 27 years in 2010 (with a pension) but then started consulting. The consulting proved to be far more successful than I ever would have guessed, so I am still adding to the stash. My pension is 100% of base expenses with nothing left over. My husband will start drawing SS next year (April 2018) at age 66. I will start drawing 50% spousal at Dec 2019 (my age 66) and then I will file for my full at end of 2023 when I turn 70 (I am the higher earner). But I am loath to withdraw any amount from savings/investments because I can't help thinking "well what if something happens in 5 years, 10 years, 15 years and I really need that money?" So, I dunno.