What if you'd held CSTL?
A $1,000 investment in Castle Biosciences, Inc. (CSTL) at the month-end close of 2019-07 would be worth $1,645 at the close of 2026-08 — +64.5% total return, dividends reinvested. The same $1,000 in the S&P 500 would be worth $2,586.
Your scenario
Result
If you'd bought $1,000 at the start of each year
Value of $1,000 invested on January 1 of each year, held to 2026-08, dividends included.
Every year, $1,000 from 2019
| Year | Value of $1,000 | Year return |
|---|---|---|
| 2019 | $1,000 | — |
| 2020 | $1,954 | +95.4% |
| 2021 | $1,247 | -36.2% |
| 2022 | $685 | -45.1% |
| 2023 | $628 | -8.3% |
| 2024 | $775 | +23.5% |
| 2025 | $1,132 | +46.0% |
| 2026 | $940 | -16.9% |
Best and worst month-end to buy
The best single month-end close to have bought CSTL was 2023-06 ($13.72): $1,000 then is $2,356 today. The worst was 2021-08 ($76.73): $1,000 then is $421.
FAQ
What would $1,000 in CSTL be worth today?
A $1,000 investment in Castle Biosciences, Inc. (CSTL) at the start of 2019 would be worth about $1,645 today, a total return of +64.5%. Dividends are reinvested in these figures.
What were the best and worst years for CSTL?
Castle Biosciences, Inc. (CSTL)'s strongest calendar year since 2019 was 2020, a +95.4% return — $1,000 held through that year became about $1,954 by year-end. Its weakest year was 2022, at -45.1%.
Does the calculator include dividends and splits?
Yes where available. Prices are adjusted for both stock splits and reinvested dividends (total return), the same measure brokerages use.
How much would $100 per month in CSTL have grown?
Investing $100 at the end of every month since 2019-07 would have grown to about $10,078 on $8,600 invested.
Did CSTL beat the S&P 500?
Over the same period, $1,000 in the S&P 500 index would be worth $2,586. CSTL trailed the S&P 500 by +36.4% in total return.
Is this investment advice?
No. Wall Street Regrets is an entertainment and education tool. Every number is a historical calculation, not a prediction, and past performance never guarantees future results.
Methodology
Castle Biosciences, Inc. (CSTL) historical total-return data from 2019-07 to 2026-08, reduced to month-end closes for the tables above.
Returns use adjusted close prices from Yahoo Finance historical data — adjusted for stock splits and reinvested dividends — the same convention used by major brokerages. A "year" scenario invests $1,000 at the prior December's month-end close and values it at the latest available month-end close. Non-USD amounts are converted at historical month-end exchange rates (Yahoo Finance): to USD on the buy date and back to your currency at the latest rate, so the return reflects the currency move as well as the asset.
Month-end resolution means intra-month extremes are not captured in tables; the calculator uses exact trading-day closes where daily data is available. Figures ignore taxes, fees, and the currency effects of non-USD listings. History is not a forecast. Wall Street Regrets is entertainment, not investment advice.
What if you'd held…
Data: adjusted close prices via Yahoo Finance. As of 2026-08. Not financial advice.