-55.88% is the change from 34 to 15
Calculation steps:
[( 15 - 34 ) ÷ 34] x 100 = -55.88%
Formula
Percentage change = [(15 - 34) / 34] x 100
Subtract the new number by the original number
15 - 34 = -19
-19 ÷ 34 = -0.5588235294117647
-0.5588235294117647 x 100 = -55.88%