(Bloomberg) — Beneath a placid surface that broke last week, chaos has been reigning all year in U.S. equities.

The evidence is in the winners and losers list, where a midyear rotation spurred by signs of an improving U.S. economy upended defensive industries and thrust banks and technology companies to the fore. By one reckoning — the degree to which winners and losers have flipflopped from the first half to the second — this has been the least orderly year since at least 1990.

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