In the previous post, I suggested reasons why you might want to create your own financial planning spreadsheet, and described the nuts and bolts of setting one up. But there’s still the problem of choosing reasonable inputs and interpreting results in a way that gives you insight into your financial future — rather than leading you astray. In this post, I go over how to make the most effective use of your spreadsheet plan: how to handle inflation, what you might assume about investment rate of return, how to do sensitivity and what-if analyses, and how to check your results against other tools. Inflation — What to Do With It…