-3.56% is the change from 646 to 623
Calculation steps:
[( 623 - 646 ) ÷ 646] x 100 = -3.56%
Formula
Percentage change = [(623 - 646) / 646] x 100
Subtract the new number by the original number
623 - 646 = -23
-23 ÷ 646 = -0.03560371517027864
-0.03560371517027864 x 100 = -3.56%