64400% is the change from 1 to 645
Calculation steps:
[( 645 - 1 ) ÷ 1] x 100 = 64400%
Formula
Percentage change = [(645 - 1) / 1] x 100
Subtract the new number by the original number
645 - 1 = 644
644 ÷ 1 = 644
644 x 100 = 64400%
Example