归结到几个原因：政府刺激政策增加债券供应、追加保证金，原油冲击，风险平价模型以及其他类似对冲基金强行平仓。但是真正重要的是后面几个原因而不是债券供给担忧。

Traders ‘Liquidating Positions Everywhere’ Are Upending Markets
Sell-off sweeps European bonds amid government stimulus plans
Equities set for another leg down after Tuesday relief rallyBy Sam Potter
(Bloomberg) — From funding stresses to headaches about trading from home, the Wall Street worry list is a long one right now. One item is creeping up that list fast: Unreliable havens.
Stocks tumbled anew on Wednesday as the turmoil sparked by the coronavirus continued to build. U.S. futures were once again pinned to their lower trading limit as pre-market trading in exchange-traded funds suggested more heavy losses.
But the most eye-catching moves were in the bond market. European government obligations including bunds tumbled at the same time as stocks in the region. Treasuries fluctuated, threatening to extend their decline a day after the biggest yield jump for 10-year U.S. bonds since 1982. A similar dynamic took hold earlier in Asia.
The synchronized drop is not something that’s supposed to happen, and it’s a threat to classic diversification strategies where bonds are used to hedge stock declines. To add insult to injury, gold — a haven for centuries — is also down in Wednesday trading.
“The worst outcome at the moment is there’s nowhere to hide