Do you think it's the Fed?
The market determines short term interest rates.
The Federal Funds Rate, which is set by the Fed, FOLLOWS 3 month T-Bill rates. It does not lead the economy. Here are some looks.Read it at Angry Bear
Who Determines Short Term Interest Rates?
Scott Fullwiler responds in the comment section:
STF said...Many believe this but it's the other way around. The tbill is based on expectations of the Fed since it's a 3 month rate and there can be a change in the funds rate that would affect holding period return. Just because statistically one comes first doesn't mean that's the causation. They should go read the Fed's transcripts and see how many times they say "the Tbill's moving so we have to change the funds rate." Doesn't happen.