-6.77% is the change from 665 to 620
Calculation steps:
[( 620 - 665 ) ÷ 665] x 100 = -6.77%
Formula
Percentage change = [(620 - 665) / 665] x 100
Subtract the new number by the original number
620 - 665 = -45
-45 ÷ 665 = -0.06766917293233082
-0.06766917293233082 x 100 = -6.77%