-3.55% is the change from 591 to 570
Calculation steps:
[( 570 - 591 ) ÷ 591] x 100 = -3.55%
Formula
Percentage change = [(570 - 591) / 591] x 100
Subtract the new number by the original number
570 - 591 = -21
-21 ÷ 591 = -0.03553299492385787
-0.03553299492385787 x 100 = -3.55%