-21.64% is the change from 402 to 315
Calculation steps:
[( 315 - 402 ) ÷ 402] x 100 = -21.64%
Formula
Percentage change = [(315 - 402) / 402] x 100
Subtract the new number by the original number
315 - 402 = -87
-87 ÷ 402 = -0.21641791044776118
-0.21641791044776118 x 100 = -21.64%