Elroy Dimson

Elroy Dimson, along with Paul Marsh and Mike Staunton at London Business School, co-authored "Triumph of the Optimists: 101 Years of Global Investment Returns" (2002), which created the world's longest and most comprehensive global equity market dataset. Their research — now the Credit Suisse Global Investment Returns Yearbook — covers 23 countries over 100+ years, establishing the long-run equity premium, the dangers of survivorship bias, and the global performance of different asset classes. This work is foundational for long-horizon asset allocation and liability-driven investment strategies. Their finding that country-level equity returns are far more dispersed than practitioners typically assume — with many historical markets delivering negative real returns over decade-long periods — provided a powerful empirical case for broad international diversification and a caution against anchoring long-run return expectations to the exceptional twentieth-century US equity performance.