Change

As in "a formula for the rate of change."

Magic phrase: "New minus old...over old." So if you have the new revenues, i.e. this year's at $100 million, and last year's revenues were $82 million...then your new-minus-old is $18 million. You put in the denominator the old revs of $82 million to get the revenue growth rate or change.

So that's 18 over 82, or 0.22. And there's your rate of change.