ChInvIA · Investment growth · Abarbanell and Bushee (1998)

Change in capital inv (ind adj)

Long minus short decile portfolio, value-weighted, market-adjusted. Quarterly, 1952Q3 to 2024Q4.

Expected return · posterior mean, % per year, averaged over the window
Next quarter
2026Q4
4.95%
95% interval 2.12% to 7.71%
Next year
2026Q4–2027Q3
4.95%
95% interval 2.09% to 7.72%
Next five years
2026Q4–2031Q3
4.95%
95% interval 1.94% to 7.77%

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

+3,430% since 1952Q3 · log scale

Past performance, annualized

Window Mean Vol. Sharpe t
1952Q3–2024Q4 5.67% 12.22% 0.46 3.95
2020Q1–2024Q4 7.98% 17.82% 0.45 1.00
2024Q1–2024Q4 0.24% 3.65% 0.06 0.06

Forecast Sharpe ratio, annualized

Window Mean 95% interval P(neg)
2026Q4 0.40 0.17 – 0.63 <0.01
2026Q4–2027Q3 0.40 0.17 – 0.63 <0.01
2026Q4–2031Q3 0.39 0.13 – 0.63 <0.01
Category
Investment growth
Form
Continuous
Data
Accounting
Sorted on
Low minus high
Names per leg
343.5 long / 346 short median · 41 at the 10th pctile
Original sample
1974–1988