28.5% with three caveats all relating to the fact we just discovered MMM this year:
First, we only started tracking spending/savings rates in April. The true number for the year is probably lower, but I'm not going to take the time to calculate it. Doing so would probably be depressing and this number makes me feel better.
Second, this number is what I call our "Quasi-savings rate" which includes both actual savings and student loan debt repayment. I figure SL payments would be money we save if we didn't have the debt. We are ruthlessly slaughtering the debt, though, and are on pace to have it paid off by fall of 2016, at which point the income will become actual savings.
Third, I prefer to look at the improvement we made this year. In April, our quasi savings rate was 10.1%. In October we hit a 50% quasi savings rate for the first time. We are making additional changes in 2016 (e.g. to health insurance) which ought to enable us to average more than 50% quasi savings rate in 2016 (knock on wood).