# “Less than” - Do you see anything wrong with this statement?

I have had a colleague me about a potential typo. The text is currently as follows:

"... whereas the XX team once had around XX support tickets a semester, that number is now 75-80% of what it used to be."

My colleague suggests it should read:

"... whereas the XX team once had around XX support tickets a semester, that number is now 75-80% less than what it used to be."

I have been looking at both of these until I am blue in the face, but I am unable to detect quite how the new phrase is justified. Perhaps the expression, taken in isolation, is poorly worded in the first place.

Any suggestions?

/luke

• "80% of X" equals 80% of X. "80% less than X" equals 20% of X. Which of the two is justified, we can't tell from the information provided. Just how much X do you have compared to before. – RegDwigнt Sep 11 '18 at 20:14

There is a clear difference in mathematical meaning between the two.

Let's assume that "what it used to be" is 100 tickets per semester.

Then the first option, "75-80% of what it used to be", is claiming that you now get 75-80 tickets per semester. That's your base rate, times 0.75 to 0.80.

The second option, "75-80% less than what it used to be", is claiming that you now get 20-25 tickets per semester. That's your base rate, minus (your base rate times 0.75 to 0.80). 100 - (100 * 0.75) = 100 - 75 = 25.

Which one you want to use depends on the actual formula that you are communicating.