The spreadsheet will run through hundreds to thousands of simulations with historical data. You can use real inflation numbers or set a fixed rate, and use the actual index/fund returns to calculate the average/standard deviation of returns to simulate the different runs. Additional money could be added (savings) or subtracted (expenses) each year. From the many simulations, confidence levels can be computed to show the different percentiles, mean, median, standard deviation, min/max end values, and successful or failed runs. Updated with 2023 returns and inflation numbers.
The cost is $30, and you can send payment through Paypal. Either by my email account (dan@55e.co), https://paypal.me/55eco, or the link below. Other payment options could be arranged. What you will get is the Google Spreadsheet, an instructional video on use of the spreadsheet, and technical support via email. Once I receive your payment, I’ll send you the Google Spreadsheet link for you to make a copy to your Google Drive account. The spreadsheet will not work with Excel. You get continuing updates via the emailed link, or if a new version comes out, I'll email you the new link.