The period that you measure someone's market performance is independent of how long they actually hold a single equity. Do you measure a day trader's performanc

The period that you measure someone's market performance is independent of how long they actually hold a single equity. Do you measure a day trader's performance over a single day? Either way - it's a moot point - (Just like the investment funds you excluded) BRK doesn't need to turn over an equity to increase their value, whatever the time period. They could never sell anything and still give increased returns to their investors.