PSIX −47.7%. Cummins +26.7%, Brunswick +10.3%, Westport Fuel Systems −11.1%, BWX Technologies −28.8%. Weekly closes, Oct 10, 2025 = 100, log scale.

End-of-day closes (Databento EOD), the last close of each week. The four peers are the largest US-listed companies by market value in PSIX’s SEC industry (Engines & Turbines) with a year of closes. It shows what the closes did; a move here is not a cause, a forecast or a call.