Marathon Petroleum Plummets 3.56% as Trading Volume Slides to 418th Rank Amid Sector Pressures and Volatile Crude Prices

On October 10, 2025, Marathon Petroleum (MPC) closed down 3.56%, with a trading volume of $0.31 billion, ranking 418th in volume among listed stocks. The decline occurred amid shifting market dynamics and sector-specific pressures.

Recent developments highlight challenges in refining margins and crude oil price volatility, which have historically influenced MPC’s stock performance. Analysts noted that seasonal demand patterns and inventory adjustments at key production hubs contributed to the day’s weakness. The company’s exposure to midstream operations also faces scrutiny as transportation costs remain elevated.

To set up this back-test precisely I need to pin down a few implementation details that aren’t fully specified yet. Could you please confirm (or modify) the following? 1. Stock universe • “All U.S. common stocks” (including ETFs) • or “Current S&P 500 constituents” • or a different universe? 2. Ranking & execution timing • Rank stocks each day by that day’s trading volume, select the top 500. • Rebalance the next trading day: – Buy (equal-weight) at the next day’s open and sell at that day’s close (1-day holding). • Is this the execution you have in mind? (If you prefer same-day close-to-close or some other convention, let me know.) 3. Cash & transaction costs • Assume 0% commissions/slippage • or specify your preferred rates. Once I have these details I can schedule the data pulls and run the portfolio back-test.