This is a far from ideal measure but it can be used to compare performance over time and to establish target rates of return.

The social discount rate is used by governments to compare the economic effects of different policy decisions over time.

That compares with 84 percent of whites in the income category, up 3.7 percentage points over the period.

A more correct procedure is to compare average temperatures over large periods of time.

This compares with a 2.1 percent gain in the third quarter of 1987 over the second.

The three of us can compare notes over dinner.

Reporting figures relative to this is the right thing to do if you want to compare trends over years and across countries.

And if it isn't, we can't compare them over an open line.

Then, he compared his excitement over the merger to "the first time I made love."

Techniques from competitor analysis can be used to compare companies over time.