美国财政部拍卖六周期国债，得标利率4.235%（5月13日为4.245%），投标倍数2.97（前次报2.77）。

Core Insights - The U.S. Treasury auctioned six-month Treasury bills with a winning yield of 4.235%, slightly down from 4.245% on May 13 [1] - The bid-to-cover ratio was 2.97, indicating stronger demand compared to the previous auction's ratio of 2.77 [1]