-6.11% is the change from 687 to 645
Calculation steps:
[( 645 - 687 ) ÷ 687] x 100 = -6.11%
Formula
Percentage change = [(645 - 687) / 687] x 100
Subtract the new number by the original number
645 - 687 = -42
-42 ÷ 687 = -0.0611353711790393
-0.0611353711790393 x 100 = -6.11%