what "bond" do you refer to?
if you refer to the credit markets -- commercial papers/corporate bonds/MBS/
high-yield bonds, the return is determined by both risk-free interest rate (
i.e. Treasury etc) and credit spread (i.e, chance of default /bankrupcy).
During the crisis last year, credit spread widened dramatically -- some part
of the credit market literally forzen in the mid of the panic.
While, the tide turned and credit spread narrows this year (so far).