-3.46% is the change from 665 to 642
Calculation steps:
[( 642 - 665 ) ÷ 665] x 100 = -3.46%
Formula
Percentage change = [(642 - 665) / 665] x 100
Subtract the new number by the original number
642 - 665 = -23
-23 ÷ 665 = -0.03458646616541353
-0.03458646616541353 x 100 = -3.46%