What if you'd held MCRB?
A $1,000 investment in Seres Therapeutics, Inc. (MCRB) at the month-end close of 2015-06 would be worth $5.64 at the close of 2026-08 — -99.4% total return, dividends reinvested. The same $1,000 in the S&P 500 would be worth $3,736.
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 2015
| Year | Value of $1,000 | Year return |
|---|---|---|
| 2015 | $1,000 | — |
| 2016 | $282 | -71.8% |
| 2017 | $289 | +2.4% |
| 2018 | $129 | -55.4% |
| 2019 | $98.32 | -23.7% |
| 2020 | $698 | +610.1% |
| 2021 | $237 | -66.0% |
| 2022 | $160 | -32.8% |
| 2023 | $39.90 | -75.0% |
| 2024 | $23.68 | -40.6% |
| 2025 | $21.20 | -10.5% |
| 2026 | $6.67 | -68.5% |
Best and worst month-end to buy
The best single month-end close to have bought MCRB was 2026-08 ($4.68): $1,000 then is $1,000 today. The worst was 2015-06 ($830): $1,000 then is $5.64.
FAQ
What would $1,000 in MCRB be worth today?
A $1,000 investment in Seres Therapeutics, Inc. (MCRB) at the start of 2015 would be worth about $5.64 today, a total return of -99.4%. Dividends are reinvested in these figures.
What were the best and worst years for MCRB?
Seres Therapeutics, Inc. (MCRB)'s strongest calendar year since 2015 was 2020, a +610.1% return — $1,000 held through that year became about $7,101 by year-end. Its weakest year was 2023, at -75.0%.
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 MCRB have grown?
Investing $100 at the end of every month since 2015-06 would have grown to about $1,624 on $13,500 invested.
Did MCRB beat the S&P 500?
Over the same period, $1,000 in the S&P 500 index would be worth $3,736. MCRB trailed the S&P 500 by +99.8% 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
Seres Therapeutics, Inc. (MCRB) historical total-return data from 2015-06 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.