Verified answer

the earth's perihelion and aphelion distances differ by 3 %; since solar radiation varies as 1/r^2, we can write

I(aphelion)/I(perihelion) = [r(ap)/r(peri)]^2=1.03^2=1.06

since r(ap)=1.03 r(peri)

this is a 6% difference in incident radiation throughout the year

for Mars, the distances vary by closer to 9%, so the ratio of energies is 1.09^2=1.19 or a 19% difference

Are you sure that that's aphelion and not simply a sterling case of perihelion?