The approximate value in US$ of the world bond market capitalization (as of 2021) is 119 trillion US$. Of this total, 46 trillion US$ is the US bond market capitalization.
In the United States, Treasury bonds are more than 1/3 of the 46 trillion US$. Other bonds are corporate bonds, mortgage-related, municipal, money markets, agency securities, and asset backed.
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The world bond market is significantly big. That also means that the bitcoin or the gold markets are relatively small
The amount of debt is enormous