Event#52tier 1live in production
index rebalance drift
cadence: Dailydata: mediumlong onlyshort only
Mechanism
When a stock is added to the S&P 500, index funds must buy it on the effective date. The announcement (typically 3-5 trading days before) triggers a front-running rally averaging +8% by effective date. Deletions show a symmetric -4% drop. Both effects partially reverse in the 20 days after effective
Data dependencies
daily_pricesAdjusted-close OHLCV for every US-listed ticker; primary price feed.
index_rebalance_eventsWorker data table — see services/worker schema.
Expected edge
Ref: Chen, Singal, *Earning Alpha by Avoiding the Index Rebalancing Crowd*, Financial Analysts Journal 2023 (avg 8.08% add-day pop, 4.85% reversal).
Illustrative pattern only
NOT a backtestIllustrative pattern only — see /app for live backtests and the actual current equity curve.
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