November 19th, 2004, 11:34 pm
There are standard analytic approaches, but the specific implementation depends on the situation. The basic idea is to consider the major risk factors in a fixed income portfolio: interest rates, currencies, credit spreads and rate volatility (possibly more if this is a specialized strategy). The manager will presumably be trying to make money by varying some of them, while eliminating exposure to others. You'll want to compute the return of a portfolio that held the same average exposure to these risk factors, but kept them constant. Then you'll see how much money was made or lost by varying exposure to each factor individually. Then you'll be left with a residual.