This doesn't calculate stats correctly for how much a map gets played.
For instance, I compared some of the contest maps. ctf_haarp_b2's daily map stats are between 5 and 9 players each day, but the average is 2.09. ctf_vector_c3's daily stats are between 3 and 6, but it's average is 9.81.
Obviously something is out of wack. And it messes up the overall list of most popular maps, which is based on the average active players.