-19.1% is the change from 670 to 542
Calculation steps:
[( 542 - 670 ) ÷ 670] x 100 = -19.1%
Formula
Percentage change = [(542 - 670) / 670] x 100
Subtract the new number by the original number
542 - 670 = -128
-128 ÷ 670 = -0.191044776119403
-0.191044776119403 x 100 = -19.1%