A good test would be to compare this summer so far with summer of 2003, which was a very nice long summer.
However, a long summer doesn't necessarily mean a lot of flying gets done. What does happen is that the first week of nice weather (preceeded by lots of bad weather) brings out a lot of pilots, but the activity tails off after that even if the good weather continues, presumably because most people exhaust their budgets, or the usual other factors put pressure on how much time they can fly.
Also, fatals are rare, not more than a few each year, and one should expect large variations in rare events anyway.