Solo stats tell more about your abilities. When I play in the full party and have at least 1 decent player (KD around 2), then I really win about 100% of the games, when all teammates have KD around 0.9-1.5 we still lose very rarely.
I play 70% solo or with one friend and have k/d around 2.45 and w/l 3.1, but if i had all teammates nearly the same stats, I think I would never lose It's always way easier to get good stats if you play with strong clan.