By | August 12 2011 1:00 PM

Heading towards the close of a memorable week, fixed income trading has settled down. On the one hand, the S&P downgrade triggered the most volatile market in a year and precipitated the sharpest decline for stocks in three-years. In part its move prompted the Fed to pull a new card from its sleeve as it declared at least a two-year freeze on interest rate policy. The drama also weakened investors' appetite for fresh government debt culminating in a weaker expression of interest at Thursday's auction of long bonds. But on the other hand the slide in yields on account of this week's action did save the taxpayer more than $600 million a year in interest costs. Whether the fall in the cost of borrowing will invigorate consumer and corporate demand for loans is another question.