So key frag drop rates discovered

I binge league. I will play consistently for weeks. then break cuz im busy. First week i get all if not most of my key frags the first two days. i will get around 3 to 6 in the first week after that it drops to one or two if i play with friends. i seem to get frags more in aram as well. I doubt its random because I just got 3 key drops in a row. Because I barely played at all this week due to work. Come back and get more key frags in an hour than last two weeks.