99.62% is the change from 261 to 521
Calculation steps:
[( 521 - 261 ) ÷ 261] x 100 = 99.62%
Formula
Percentage change = [(521 - 261) / 261] x 100
Subtract the new number by the original number
521 - 261 = 260
260 ÷ 261 = 0.9961685823754789
0.9961685823754789 x 100 = 99.62%