Coefficient of Variation = 20 .25 Coefficient of Variation = LEGEND Gamma Distribution Lognormal Distribution Gamma Distribution -_Lognormal Distribution Density Function 134 2 o e& 2 a 104 = a c & 0 **] 0 64 54 00 oO Y os T 1 — 1s ” 2 X Value 7 265 T 3 35 X Value Coefficient of Variation = 1.00 12 Coefficient of Variation = 1.50 40 remem X Value Fig. 1. ————~ Gamme Distribution atte tree normal Distribution 354 Density Function Density Function ——— Gamma Distribution 304 N e . 779 10 0 os 1 18 2 X Value 25 Comparison of gamma and lognormal probability density 3 functions with expected value of unity and four values of the coefficient of variation. 35