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MED vs SPY: Correlation

How closely do MEDIFAST INC (MED) and SPDR S&P 500 ETF Trust (SPY) trade together? Their weekly returns over three years give a correlation of 0.21, which is weak.

Data as of 2026-08-27 · refreshed every trading day · weekly returns · methodology

Correlation (3Y)
0.21
weak
Correlation (1Y)
0.45
last 12 months
Correlation (5Y)
0.28
long-run
Ann. covariance
142.2
%² · weekly, annualized

How correlated are MED and SPY?

Over the past 3 years, MED and SPY moved with a correlation of 0.21, which is weak. Lately the two have moved closer together, with the 1-year correlation at 0.45 versus 0.21 over 3 years. Over 5 years the correlation is 0.28, and the annualized covariance of weekly returns is 142.2 %².

SPY is close to the least connected end of MED's tracked universe, ranking #8 of 12. The last year tells two different stories: SPY led by 35.3 percentage points, -14.7% for MED against +20.6% for SPY. Note the risk asymmetry: MED runs 3.3 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.

MED vs SPY: side by side

MED (MEDIFAST INC)SPY (SPDR S&P 500 ETF Trust)
1-year return-14.7%+20.6%
5-year return-94.1%+82.4%
Volatility (ann.)47.7%14.5%
Beta vs S&P 5000.681.00
Max drawdown (3Y)-88.8%-18.8%
Market cap$0.1B
P/E (trailing)
Dividend yield0.00%1.01%
Expense ratio0.09%
Assets under management$795.3B
Sector / categoryUS ListedETF · US Large Cap
Higher yield: SPY 1.01% vs 0.00%Smaller drawdown: SPY -18.8% vs -88.8%Higher 5y return: SPY +82.4% vs -94.1%

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.

-29%0%+21%2025-09-052026-08-27
Both assets over the last year, indexed to 100 at the starting week. MED · SPY

Year-by-year returns

YearMEDSPY
2022-42.3%-18.2%
2023-38.3%+26.2%
2024-73.8%+24.9%
2025-39.4%+17.7%
2026+13.9%+13.7%

Calendar-year price returns; the current year is year-to-date as of the data date above.

Are MED and SPY good diversifiers for each other?

Reasonably. At 0.21, MED and SPY keep a meaningful degree of independence, and combining them has historically reduced portfolio volatility.

FAQ

What is the correlation between MED and SPY?

The MED/SPY correlation stands at 0.21 on a 3-year window (1 year: 0.45, 5 years: 0.28), computed from weekly returns as of 2026-08-27.

Is SPY a good diversifier for MED?

Reasonably. At 0.21, MED and SPY keep a meaningful degree of independence, and combining them has historically reduced portfolio volatility.

What does a correlation of 0.21 mean?

On the −1 to +1 scale, 0.21 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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MED vs SPY: 3-year weekly correlation 0.21MED vs SPY0.21

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Hubs: MED correlations · SPY correlations