-3.39% is the change from 620 to 599
Calculation steps:
[( 599 - 620 ) ÷ 620] x 100 = -3.39%
Formula
Percentage change = [(599 - 620) / 620] x 100
Subtract the new number by the original number
599 - 620 = -21
-21 ÷ 620 = -0.03387096774193549
-0.03387096774193549 x 100 = -3.39%