美国至5月15日4周国债竞拍-得标利率 4.22%，前值4.225%。

Core Viewpoint - The auction yield for U.S. Treasury bonds as of May 15 is reported at 4.22%, slightly down from the previous value of 4.225% [1] Group 1 - The current yield indicates a marginal decrease, reflecting slight changes in market conditions [1]