-93.09% is the change from 217 to 15
Calculation steps:
[( 15 - 217 ) ÷ 217] x 100 = -93.09%
Formula
Percentage change = [(15 - 217) / 217] x 100
Subtract the new number by the original number
15 - 217 = -202
-202 ÷ 217 = -0.9308755760368663
-0.9308755760368663 x 100 = -93.09%