Since one of the big advantages of ESPlanner is that it plans all your assets, not just your portfolio of securities, why not use Monte Carlo simulation for the inflation rate? We know that a fixed inflation rate even with one reset represents only one of many possibilities.
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The short answer is "state variable".
Basically the amount of time it takes to do a Monte Carlo simulation depends on the number of state variables. The simulation is [roughly] an n**x problem where x is the number of state variables. At the moment, with a married couple, the MC takes about 2 to 3 minutes [on a fairly robust processor]. Adding another state variable would, at least, double that amount of time and maybe worse.
At some point the product becomes useless commercially due to the amount of time it takes to return results and a trade off was made [admittedly 10 to 15 years ago] to keep the number of state variables as low as possible. Given what's happened to processor and memory speeds since then it may be past time to revisit that decision but there are other fruit to be picked that don't require quite as much work.
Best,
Dick Munroe
Moore's law versus Munroe's law. lol ... Dick, I'm not even sure what I mean by that, it just jumped out at me while reading your post. I think it would be *nice* to have the *option* to get a slower but better response. Of course, some folks would turn on all the options all the time and then complain it was too slow, you'd get bad press, go out of business, and we'd all be out of luck.
Maybe you need to market an "ESP Cray" version. Throw in a few more state variables and you could charge an extra $50 and target only folks with Cray-like PCs. This could be the killer app that pushes Intel to the next level. :)
We're kind of hoping to head that direction with a web based version of ESPlanner (and a few bushels of money). We could run a web version, backed by a computation server (to go along with the computation engine) that was seriously major iron with 100s of gigabytes of physical memory or a RAIC (redundant array of inexpensive computers) or perhaps on the Amazon cloud.
But, unfortunately, that's for the future.
Best,
Dick Munroe
I just purchased a PC with a Quad processor for $700 including display and printer (8 GB of memory and a terabyte hard drive). I vote for the ESP Cray version.