50.85% is the change from 645 to 973
Calculation steps:
[( 973 - 645 ) ÷ 645] x 100 = 50.85%
Formula
Percentage change = [(973 - 645) / 645] x 100
Subtract the new number by the original number
973 - 645 = 328
328 ÷ 645 = 0.5085271317829457
0.5085271317829457 x 100 = 50.85%