By: Felicity Hurley
The U.S. Treasury market, the deepest and most liquid in the world, operates with a peculiar duality: less than 4% of its $30 trillion outstanding debt—comprising the most recently issued Treasuries known as on-the-run securities—drives 65% of daily trading volume. The remaining 96%, consisting of older, off-the-run issues, trades far less frequently, creating a two-tiered market where liquidity and trading dynamics diverge sharply.














