-83.49% is the change from 109 to 18
Calculation steps:
[( 18 - 109 ) ÷ 109] x 100 = -83.49%
Formula
Percentage change = [(18 - 109) / 109] x 100
Subtract the new number by the original number
18 - 109 = -91
-91 ÷ 109 = -0.8348623853211009
-0.8348623853211009 x 100 = -83.49%