After reading an interesting posting by Iofoto (aka Ron Chapple)
It was an interesting discover especially to analyze the year trend broken down by month. I found out that mine was almost exactly as his, with January starting slowly (is a a month that for most people usually starts after the 7th) February and March with first signs of picking up the rythm and April-May being both very good months.
June July and August are usually mostly flat and from September sales start again to rise, hitting a top between October and November. December is the month with less sales in all the year.
This yearly trends I have checked here at Dreamstime for my portfolio (thanks to the very good graph that is already there in your management section) and it is constantly repeating.
Is a kind of analysys that Pro (as Iostock) do constantly to improve their work and their success.