-41.18% is the change from 170 to 100
Calculation steps:
[( 100 - 170 ) ÷ 170] x 100 = -41.18%
Formula
Percentage change = [(100 - 170) / 170] x 100
Subtract the new number by the original number
100 - 170 = -70
-70 ÷ 170 = -0.4117647058823529
-0.4117647058823529 x 100 = -41.18%