-69.05% is the change from 42 to 13
Calculation steps:
[( 13 - 42 ) ÷ 42] x 100 = -69.05%
Formula
Percentage change = [(13 - 42) / 42] x 100
Subtract the new number by the original number
13 - 42 = -29
-29 ÷ 42 = -0.6904761904761905
-0.6904761904761905 x 100 = -69.05%