I once heard that the most reported dog bites are from Labs, might be wrong, but it makes one scratch their head.
I think this is true, but the difference is in the numbers of the dog breeds. Labs may more often be the biter, but they are also 10-20 times more popular of a dog than pits. One should probably look at this in a bite per thousand dogs (of a specific breed). And I don't know that I've ever seen anyone try to tackle this.