The change in industry mix from 1900 to 2026

> Of the US firms listed in 1900, some 80% of their value was in industries that are small or extinct today, including railroads, textiles, iron, coal and steel. Meanwhile, 70% of today's companies in the US come from industries that were small or non-existent in 1900. Technology and healthcare were almost totally absent from stock markets in 1900. > Investors often associate new technologies with "bubbles" and…