We were well over 100% at our current projected spending level upon my retirement. When I say well over, I used the “investigate” tab to see how high our spending could go, and we had upward room of about 50% higher spending before dropping below 100% success. That said however, all of these analysis tools (FIRECalc,I-ORP, Portfolio Visualizer, etc. etc.) simply provide a guesstimate based upon various assumptions. Fact-based and historically driven, yes, but still a guesstimate.
FIRECalc’s main assumption, as they say on the site, is whether your portfolio and spending plan would have weathered everything the market has had thrown at it since 1871, including two world wars, The Great Depression and so on. That’s all well and good but needless to say if TSHTF all bets are off.
One of the input assumptions loaded was life expectancy. Actuarial results for me say a life expectancy of 93 and for DW 96. In light of both of our family medical histories and actual life spans I find both of those numbers overly optimistic/conservative. Realty for DW and myself is more like 85 plus or minus a few years. So that has a large impact on portfolio success as well.
In modeling for our retirement I looked at a worst case scenario figuring if we could have success under those assumptions then we should be fine, come what may...