BM · Valuation · Stattman (1980)

Book to market, original (Stattman 1980)

Long minus short decile portfolio, value-weighted, market-adjusted. Quarterly, 1951Q3 to 2024Q4.

Expected return · posterior mean, % per year, averaged over the window
Next quarter
2026Q4
5.17%
95% interval 0.95% to 9.50%
Next year
2026Q4–2027Q3
5.12%
95% interval 0.83% to 9.53%
Next five years
2026Q4–2031Q3
4.94%
95% interval 0.33% to 9.63%

Forecast made 16 Sep 2026, conditioning on this portfolio's OAP returns, which end 2024Q4. The 7 quarters between then and 2026Q4 are unobserved and are integrated out under the model.

Cumulative market-adjusted return

+1,692% since 1951Q3 · log scale

Past performance, annualized

Window Mean Vol. Sharpe t
1951Q3–2024Q4 5.47% 17.78% 0.31 2.64
2020Q1–2024Q4 15.66% 25.56% 0.61 1.37
2024Q1–2024Q4 3.30% 7.46% 0.44 0.44

Forecast Sharpe ratio, annualized

Window Mean 95% interval P(neg)
2026Q4 0.29 0.05 – 0.54 0.01
2026Q4–2027Q3 0.28 0.04 – 0.51 0.01
2026Q4–2031Q3 0.23 0.01 – 0.46 0.02
Category
Valuation
Form
Continuous
Data
Accounting
Sorted on
High minus low
Names per leg
152 long / 154 short median · 40 at the 10th pctile
Original sample
1962–1976