BST vs CII: Correlation
BlackRock Science and Technology Trust (BST) and BlackRock Enhanced Large Cap Core Fund, Inc. (CII) show a very strong relationship: their 3-year correlation of weekly returns is 0.83.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are BST and CII?
On 3 years of weekly data the BST/CII correlation comes out at 0.83, very strong, meaning they move nearly in lockstep. Recent behaviour matches the longer record: 0.79 over 1 year against 0.83 over 3. The 5-year figure is 0.83, and annualized covariance runs at 323.6 %².
Within BST's tracked universe of 25 assets, CII comes in at #6 by 3-year correlation. Over the last 12 months BST came out ahead by 9.7 percentage points (+40.7% against +31.0%).
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.
BST vs CII: side by side
| BST (BlackRock Science and Technology Trust) | CII (BlackRock Enhanced Large Cap Core Fund, Inc.) | |
|---|---|---|
| 1-year return | +40.7% | +31.0% |
| 5-year return | +46.7% | +85.9% |
| Volatility (ann.) | 22.2% | 17.7% |
| Beta vs S&P 500 | 1.27 | 0.97 |
| Max drawdown (3Y) | -23.4% | -21.1% |
| Market cap | – | $1.0B |
| P/E (trailing) | 6.9 | 4.8 |
| Dividend yield | 0.00% | 8.38% |
| Sector / category | US Listed | US Listed |
Year-by-year returns
| Year | BST | CII |
|---|---|---|
| 2022 | -38.3% | -13.2% |
| 2023 | +30.1% | +18.5% |
| 2024 | +18.0% | +12.7% |
| 2025 | +23.7% | +37.8% |
| 2026 | +30.9% | +11.2% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are BST and CII good diversifiers for each other?
No. With a correlation of 0.83, BST and CII move nearly in lockstep, so holding both adds very little diversification.
FAQ
What is the correlation between BST and CII?
As of 2026-08-27, the correlation of weekly returns between BST and CII is 0.83 over 3 years, 0.79 over 1 year and 0.83 over 5 years.
Is CII a good diversifier for BST?
No. With a correlation of 0.83, BST and CII move nearly in lockstep, so holding both adds very little diversification.
What does a correlation of 0.83 mean?
Correlation ranges from −1 to +1. Values near +1 mean two assets move together, near 0 that they move independently, and negative values that they tend to move in opposite directions. It measures co-movement, not performance.
Use this data
$ curl https://www.pairbook.io/api/v1/pairs/bst-vs-cii.json
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Related comparisons
Hubs: BST correlations · CII correlations
