69.05% is the change from 391 to 661
Calculation steps:
[( 661 - 391 ) ÷ 391] x 100 = 69.05%
Formula
Percentage change = [(661 - 391) / 391] x 100
Subtract the new number by the original number
661 - 391 = 270
270 ÷ 391 = 0.690537084398977
0.690537084398977 x 100 = 69.05%