-33.98% is the change from 977 to 645
Calculation steps:
[( 645 - 977 ) ÷ 977] x 100 = -33.98%
Formula
Percentage change = [(645 - 977) / 977] x 100
Subtract the new number by the original number
645 - 977 = -332
-332 ÷ 977 = -0.3398157625383828
-0.3398157625383828 x 100 = -33.98%