Shift4 Payments Stumbles 3.4 as $240M Surge Propels It to 422nd in U.S. Dollar Volume Rankings

On September 24, 2025, Shift4 Payments (FOUR) closed down 3.40% despite a 59.06% surge in trading volume to $240 million, ranking 422nd in dollar volume among U.S. equities. The decline came amid mixed market sentiment toward payment sector stocks following broader market volatility.

Recent developments suggest shifting investor priorities in the fintech space. While the company’s high-volume day highlighted renewed short-term interest, the price action indicated caution among institutional participants. Analysts noted that the stock’s performance diverged from recent momentum seen in peer groups, though no company-specific earnings or guidance updates were disclosed to directly influence the move.

To run this back-test precisely I need to pin down a few implementation details: 1. Market universe • Should we look at all U.S. listed common stocks (NYSE + NASDAQ + NYSE Arca), or a different universe (e.g., only S&P 1500 constituents, only NASDAQ stocks, etc.)? 2. Ranking & weighting logic • Each trading day we rank stocks by that day’s dollar trading volume and pick the top 500, correct? • Do we hold the basket equally-weighted (1/500 each), or apply another weighting rule (e.g., volume-weighted)? 3. Trade prices • Enter at that day’s close and exit at next day’s close (standard “close-to-close” test), or use next day’s open for the exit? 4. Practical considerations • A daily 500-stock basket from 2022-01-03 through today involves roughly 10,000 distinct tickers and over 3 million price points. • Our current back-test engine handles single-ticker or event-based tests natively; to run a multi-asset portfolio test I would pre-aggregate the portfolio’s daily P&L into a synthetic index and feed that into the engine. That works fine, it just takes longer to download the raw data.