31.94% is the change from 645 to 851
Calculation steps:
[( 851 - 645 ) ÷ 645] x 100 = 31.94%
Formula
Percentage change = [(851 - 645) / 645] x 100
Subtract the new number by the original number
851 - 645 = 206
206 ÷ 645 = 0.31937984496124033
0.31937984496124033 x 100 = 31.94%