TSMC Slumps 1.44% on $3.25 Billion Trade (24th Most Active) as Clients Shift Priorities

On September 25, 2025, TSMC (TSM) closed down 1.44% despite a trading volume of $3.25 billion, ranking 24th in daily market activity. The decline followed mixed signals from recent business updates and evolving industry dynamics, though no single event directly triggered the drop.

Recent developments highlighted include adjustments in client order priorities for advanced chip production, with some customers shifting focus to cost-optimized solutions amid softer end-market demand. Analysts noted that while TSMC maintains its leadership in cutting-edge manufacturing, near-term revenue visibility remains constrained by sector-wide inventory rebalancing. Supply chain partners also reported delayed tooling shipments, potentially affecting fourth-quarter capacity expansion plans.

To run this back-test accurately we need to nail down a few practical details up-front: 1. Universe • Do you want to scan all U.S. listed common stocks each day, or limit the search to a specific index (e.g., S&P 500 constituents)? • If it’s “all U.S. stocks,” are OTC / ADRs included or excluded? 2. Ranking logic • Should the “top 500 by trading volume” be selected using the previous day’s volume (so today’s portfolio is based on yesterday’s volume ranking), or do we form the portfolio at today’s close using today’s volume? • Equal-weighted allocation across the 500 names each day? 3. Execution prices & holding period • Enter at next day’s open and exit at the following day’s open? …or enter at the close and exit at the next close? • Any transaction-cost or slippage assumptions? Once we firm up those items I’ll generate the data-retrieval plan and run the back-test.