CSTLCASTLE BIOSCIENCES INC— growth of $10,000
A total-return backtest of a $10,000 investment in this stock, grown over about 7 years on real split- and dividend-adjusted prices and compared against the same amount in the S&P 500 (SPY). The equity curve and the risk/return stats — CAGR, volatility, Sharpe, Sortino and max drawdown — are engine-computed from historical prices, with no LLM. This is a historical backtest, not a prediction: past performance does not predict future results.
Growth of $10,000
vs SPY| Metric | CSTL | SPY |
|---|---|---|
| End value | $12.5K | $27.4K |
| Total return | +25.2% | +173.9% |
| CAGR | +3.3% | +15.4% |
| Volatility | 73.9% | 19.6% |
| Sharpe | 0.36 | 0.64 |
| Sortino | 0.55 | 0.89 |
| Max drawdown | -88.0% | -33.8% |
Based on 1763 trading days, 2019-07-25 → 2026-07-30 · risk-free 3.82% (current short-Treasury, held constant)
A total-return backtest over real split- and dividend-adjusted prices: how a one-time $10,000 investment held to today would have grown, versus SPY over the same window. A disclosed historical statistic — NOT a prediction, a guarantee, or investment advice. Past performance does not predict future results.
How the backtest works
- $10,000 at the start. The same fixed amount is invested in the stock and, for comparison, in the S&P 500 (SPY) on the first day of the window, and its value is tracked to today.
- Total return, not price-only. Prices are split- and dividend-adjusted, so the curve reflects reinvested dividends and share splits — the real economic outcome of buying and holding.
- CAGR = the compound annual growth rate that turns the starting $10,000 into the ending value over the window; it smooths a bumpy path into one annualised figure.
- Volatility = the annualised standard deviation of returns (how much the value swings); Sharpe and Sortino divide return-above-the-risk-free-rate by that risk (Sortino counts only downside swings). Higher ratios = more return per unit of risk.
- Max drawdown = the largest peak-to-trough decline along the way — the worst loss you would have sat through before recovering.
- A historical backtest, not a forecast. Every figure is engine-computed from past prices; a stat is shown only when it is computable (otherwise "—", never a fabricated 0). Past performance does not predict future results.
This page is a total-return backtest over real historical prices — not a prediction, price target or investment advice. Past performance does not predict future results. Source: split- and dividend-adjusted prices; for reference only.