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select *
into #t
from
(
values
('2020-01-01', 0.10),
('2020-02-01', 0.20),
('2020-03-01', 0.30)
) d ([Date], [Return]);
3 rows affected
SELECT *,
100 * EXP(SUM(LOG(1 + [Return])) OVER (ORDER BY [Date])) [Index]
FROM #t
| Date | Return | Index |
|---|---|---|
| 2020-01-01 | 0.10 | 110 |
| 2020-02-01 | 0.20 | 132 |
| 2020-03-01 | 0.30 | 171.6 |