FTCI vs SPY: Correlation
How closely do FTC Solar, Inc. (FTCI) and SPDR S&P 500 ETF Trust (SPY) trade together? Their weekly returns over three years give a correlation of 0.31, which is moderate.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are FTCI and SPY?
On 3 years of weekly data the FTCI/SPY correlation comes out at 0.31, moderate. The link has tightened recently: the 1-year correlation (0.46) runs above the 3-year figure (0.31). The 5-year figure is 0.33, and annualized covariance runs at 544.9 %².
SPY is close to the least connected end of FTCI's tracked universe, ranking #8 of 12. Their recent paths diverged sharply: over the last 12 months SPY outperformed by 83.0 percentage points (-62.4% for FTCI against +20.6% for SPY). Note the risk asymmetry: FTCI runs 8.5 times the annualized volatility of the other leg, so equal-weighting the two is not an equal-risk position.
How is this computed?
Pearson correlation on weekly returns: ρ(A,B) = cov(rA, rB) / (σA · σB), over windows of 52, 156 and 260 weeks. Covariance is annualized (×52) and expressed in %². Full definitions on the methodology page.
FTCI vs SPY: side by side
| FTCI (FTC Solar, Inc.) | SPY (SPDR S&P 500 ETF Trust) | |
|---|---|---|
| 1-year return | -62.4% | +20.6% |
| 5-year return | -97.8% | +82.4% |
| Volatility (ann.) | 122.6% | 14.5% |
| Beta vs S&P 500 | 2.61 | 1.00 |
| Max drawdown (3Y) | -90.4% | -18.8% |
| Market cap | – | – |
| P/E (trailing) | – | – |
| Dividend yield | 0.00% | 1.01% |
| Expense ratio | – | 0.09% |
| Assets under management | – | $795.3B |
| Sector / category | US Listed | ETF · US Large Cap |
SPY is a Large Blend fund from State Street Investment Management: $795.3B under management, 504 holdings, a 0.09% expense ratio, a 1.01% trailing dividend yield.
Year-by-year returns
| Year | FTCI | SPY |
|---|---|---|
| 2022 | -64.6% | -18.2% |
| 2023 | -74.1% | +26.2% |
| 2024 | -20.5% | +24.9% |
| 2025 | +98.0% | +17.7% |
| 2026 | -77.7% | +13.7% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are FTCI and SPY good diversifiers for each other?
Yes, to a useful degree: a correlation of 0.31 leaves real independence between the two, which historically damped combined volatility.
FAQ
What is the correlation between FTCI and SPY?
The FTCI/SPY correlation stands at 0.31 on a 3-year window (1 year: 0.46, 5 years: 0.33), computed from weekly returns as of 2026-08-27.
Is SPY a good diversifier for FTCI?
Yes, to a useful degree: a correlation of 0.31 leaves real independence between the two, which historically damped combined volatility.
What does a correlation of 0.31 mean?
On the −1 to +1 scale, 0.31 describes how much the two returns move together: +1 is lockstep, 0 is independence, negative values mean opposite directions. It says nothing about which performed better.
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Related comparisons
Hubs: FTCI correlations · SPY correlations
