May 24th, 2012, 5:34 pm
3s1s markets are quoted in the brokers. Basically 3s1s is a credit indicator. In theory, you would rather lend money for 1m, compared to 3m. Thus as the basis goes to the right, there is more of a credit concern. The way I have always looked at the market is in 3m swaps versus 1m libor (3 periods of 1m libor, versus a fixed period of 3m libor). Currently, 1y 3s1s is close to 22bps (pay 1m + 22bps to rec 3m libor flat)