-67.65% is the change from 170 to 55
Calculation steps:
[( 55 - 170 ) ÷ 170] x 100 = -67.65%
Formula
Percentage change = [(55 - 170) / 170] x 100
Subtract the new number by the original number
55 - 170 = -115
-115 ÷ 170 = -0.6764705882352942
-0.6764705882352942 x 100 = -67.65%