-94.7% is the change from 642 to 34
Calculation steps:
[( 34 - 642 ) ÷ 642] x 100 = -94.7%
Formula
Percentage change = [(34 - 642) / 642] x 100
Subtract the new number by the original number
34 - 642 = -608
-608 ÷ 642 = -0.9470404984423676
-0.9470404984423676 x 100 = -94.7%