You might be interest in this book (from another post)
This book if free for a few days and maybe of interest. Go to the books on the left side and click download. Next page is for a free down load until Jan 10th. It will touch on the 4% rule which comes out to be 3.8% to my reading of the book.
http://www.retirementoptimizer.com/
70%, 80% and over 100% are all numbers that come up. You need to make up a budget.
Costs will probably increase in the medical expense area and some taxes such as social security will decrease or end.
Then add in spending to fill in your free time. This could get you over the 100% mark because you are not going to TV to sit and watch TV.
From you description I can see a budget of 33% for basic living expense (except income tax), and another 33% for eating out, vacations, charity etc. This includes income taxes.