-2.9% is the change from 620 to 602
Calculation steps:
[( 602 - 620 ) ÷ 620] x 100 = -2.9%
Formula
Percentage change = [(602 - 620) / 620] x 100
Subtract the new number by the original number
602 - 620 = -18
-18 ÷ 620 = -0.02903225806451613
-0.02903225806451613 x 100 = -2.9%