Variables Symbol -1 0 +1
HsDc X1 0.917 1.673 2.222 2.771 3.527
DcHs X2 0.125 0.324 0.469 0.613 0.813
dpav/Dc X3 0.0405 0.0413 0.0420 0.0426 0.0435
Gsf/Gmf X4 405 5.08 5.5 5.92 6.5
R X5 1.3 2.0 2.5 3.0 3.7
Table 2: Level of independent variables.