BlackRock Shares Plummets 0.33% as Trading Volume Tumbles 39.72% to Rank 347th Among U.S. Equities

On September 24, 2025, BlackRock (BLK) closed down 0.33% with a trading volume of $0.29 billion, ranking 347th among U.S. equities by volume. The decline marked a 39.72% drop from the previous day's turnover, indicating reduced short-term market participation in the asset manager's shares.

Analysts noted that the muted trading activity may reflect broader market consolidation following recent volatility in bond yields and equity valuations. While BlackRock's core ETF business remains resilient amid shifting investor preferences, the lack of new product launches or strategic announcements in recent weeks has limited catalysts for near-term momentum. Institutional flows into fixed-income funds continued to outpace equity inflows, though this trend has shown signs of stabilizing in Q3.

For backtesting purposes, the following parameters require confirmation: 1. **Universe**: Specify whether to include all U.S. common stocks (~4,000) or restrict to indices like Russell 3000/S&P 500. Non-U.S. markets need explicit clarification. 2. **Weighting/Rebalancing**: Define equal-weight (dollar-neutral positions) vs. value-weighted (market-cap or volume-based). Transaction cost assumptions (e.g., 5 basis points per trade) must be outlined. 3. **Execution Method**: Confirm close-to-close trading (enter at day's close, exit at next day's close) as standard practice.

If the default settings (U.S. stocks, equal-weight, no transaction costs, close-to-close execution) are acceptable, testing can proceed immediately with the provided framework.