MRK vs MRNA: Correlation
How closely do Merck & Co. (MRK) and Moderna (MRNA) trade together? Their weekly returns over three years give a correlation of 0.40, which is moderate.
Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology
How correlated are MRK and MRNA?
On 3 years of weekly data the MRK/MRNA correlation comes out at 0.40, moderate. The past 12 months show a weaker link (0.30) than the 3-year average (0.40). The 5-year figure is 0.32, and annualized covariance runs at 1116.9 %².
Within MRK's tracked universe of 34 assets, MRNA comes in at #18 by 3-year correlation. Correlation aside, the last 12 months split them widely, with MRNA ahead by 385.0 points (+83.8% versus +468.8%). The relationship is regime-dependent: the rolling one-year correlation swung between 0.04 and 0.64 over the past three years, so this pair behaves very differently depending on the market environment. Note the risk asymmetry: MRNA runs 3.6 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.
MRK vs MRNA: side by side
| MRK (Merck & Co.) | MRNA (Moderna) | |
|---|---|---|
| 1-year return | +83.8% | +468.8% |
| 5-year return | +128.5% | -61.5% |
| Volatility (ann.) | 27.9% | 100.7% |
| Beta vs S&P 500 | 0.28 | 0.98 |
| Max drawdown (3Y) | -43.4% | -86.6% |
| Market cap | $368.9B | $57.0B |
| P/E (trailing) | 121.6 | – |
| Dividend yield | 2.17% | 0.00% |
| Sector / category | Health Care | Health Care |
Year-by-year returns
| Year | MRK | MRNA |
|---|---|---|
| 2022 | +49.4% | -29.3% |
| 2023 | +1.0% | -44.6% |
| 2024 | -6.3% | -58.2% |
| 2025 | +9.8% | -29.1% |
| 2026 | +44.1% | +384.1% |
Calendar-year price returns; the current year is year-to-date as of the data date above.
Are MRK and MRNA good diversifiers for each other?
Reasonably. At 0.40, MRK and MRNA keep a meaningful degree of independence, and combining them has historically reduced portfolio volatility.
FAQ
What is the correlation between MRK and MRNA?
As of 2026-08-27, the correlation of weekly returns between MRK and MRNA is 0.40 over 3 years, 0.30 over 1 year and 0.32 over 5 years.
Is MRNA a good diversifier for MRK?
Reasonably. At 0.40, MRK and MRNA keep a meaningful degree of independence, and combining them has historically reduced portfolio volatility.
What does a correlation of 0.40 mean?
A reading of 0.40 sits on a scale from −1 (opposite moves) through 0 (unrelated) to +1 (identical moves). Correlation captures direction, not magnitude or performance.
Use this data
$ curl https://www.pairbook.io/api/v1/pairs/mrk-vs-mrna.json
Markdown for the live badge, attribution link included:
[](https://www.pairbook.io/pair/mrk-vs-mrna/)
No key needed, free to use. Full endpoint list in the API documentation.
Related comparisons
Hubs: MRK correlations · MRNA correlations
