The calculator
Each of the 646 tickers has a full calculator with amount, buy date, sell date, monthly investing and a share card. Pick a ticker, an amount and a buy date here to open it.
What it computes
- Price return: adjusted for stock splits, dividends not included.
- Month-end dates: a date resolves to the last close of the month it falls in, and the result says which close it used.
- Dollar-cost averaging: add a fixed amount at each month-end on top of your starting amount.
- Best and worst timing: the perfect and the terrible entry point inside your window, and what each would have made.
- Regret verdict: anything from "you actually won by selling" to "legacy-level".
How to share a result
Every result has a URL that reopens it and a PNG card you can download. The card shows the ticker, the amount and the number. Post it in the group chat where someone sold in 2020.
Limits
Taxes and trading fees are not modeled, so a real account would have kept less.