degree fitting curve

p1 = 4.088 (-2.889, 11.07)

p2 = -45.35 (-106.2, 15.47)

p3 = 208.7 (-1.841, 419.2)

p4 = -512.5 (-880.1, -144.9)

p5 = 716.8 (378.4, 1055)

p6 = -560.3 (-714.5, -406.1)

p7 = 217.5 (190.7, 244.4)

x = distance

f(x) = p1*x^6 + p2*x^5 + p3*x^4 + p4*x^3 + p5*x^2 + p6*x + p7