Question 1083683
percent increase from a given number is the increase divided by the original number.
percent decrease is the amount decreased divided by the original number.
if one goes from 90 to 100, that is an 11% increase, 10/90
but if one goes from 100 to 90, that is a 10% decrease, 10/100.  Despite getting back to the same number, the percent change is not the same going up and coming down.