Commentary 
It was very early in the morning, U.S. time, and the 4-week U.S. Treasury bill then being traded all over Asia suddenly captured a huge bid. At around 3:30 am EDT, May 11, the equivalent yield on this particular short-term instrument ticked lower and lower. Two hours later, around 5:30 am, the rate had fallen below 0.50 percent (50 basis points) from around 0.52 percent where it had been trading since the afternoon before.
This scramble for bills didn’t stop there. On that particular day, the bidding would keep going in irregular intervals until the 4-week yield finally reached its ultimate daily low of 0.487 percent just before 8:30 am.
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