Sample

Equation

Coefficient (r2)

PPM

y = −2E−05X² + 0.0005X + 0.1126

0.9924

PMA

y = −5E−05X² + 0.1084X − 2.4083

0.9775

PMB

y = −6E−05X²+ 0.0952X + 5.005

0.9962

PMC-1

y = −6E−05X² + 0.1005X − 5.26

0.9951