[Ifeffit] Consultation on Reduced Chi2

Dear list, I am back with a new consultation on EXAFS fitting within Artemis. I have made a fit and obtained a reduced Chi2 value of 391 and R-factor of 0.014 using 9 variables. Then I have added two more paths increasing the number of variables up to 12 and then I obtained a reduced Chi2 of 3039 and R-factor of 0.007. I am a little surprised by the huge increase of reduced Chi2 while R-factor decreases down to half. What could be the cause of this large increase? Does it mean that it is not worth to add these new paths? As always, thank you in advance Yours, Jesús