-1.93% is the change from 621 to 609
Calculation steps:
[( 609 - 621 ) ÷ 621] x 100 = -1.93%
Formula
Percentage change = [(609 - 621) / 621] x 100
Subtract the new number by the original number
609 - 621 = -12
-12 ÷ 621 = -0.01932367149758454
-0.01932367149758454 x 100 = -1.93%