I grew up skateboarding it was fun. I didn't think about money I didn't know how much professional skateboarders made. I just knew that if I became a professional skateboarder I would achieve a lot and get to travel and do these great things.
Trust your gut instinct over spreadsheets. There are too many variables in the real world that you simply can't put into a spreadsheet. Spreadsheets spit out results from your inexact assumptions and give you a false sense of security. In most cases your heart and gut are still your best guide.