I would like to create a formula in QPR Metrics where an overall percentage performance rating does not go below 0% or beyound 100%. For example in measuring turn-around times, the target will be 5 days which will be 100% and the alarm 8 days which is 0%. If the actual is less than 5 days the percenatge rating should still be 100% and no further. If the actual is beyound 8 days, the percenatge rating should be 0% and should not be a nigative figure. How do I go about creating a formula to meet these requirements?