Rankings are such incredible horseshit I just can't even begin to walk that road of insanity... You simply can't "Rank" teams on a global scale when 4 of those teams play over 50% of the cricket in their own conditions, or at home and almost-never tour to places like Zimbabwe, New Zealand or South Africa (and when they do, they get murdered more often than not). Australia haven't played in NZ for over 5 years (or more, I can't remember) and we live THREE HOURS away. Australia play in PERTH more often than they do in Auckland. Pakistan roam the globe and never play at home, Zimbabwe barely get out for a coffee with most countries, let alone an India or England... who go down 7 wickets for 11 runs more often than they do tour New Zealand. My list goes on... and then India, England and Australia play more International cricket than Zimbabwe, Ireland, New Zealand, West Indies, Bangladesh and Pakistan so they get more "points" of whatever devil science and entrail reading the ICC does to stick teams on a list for these tournaments. By comparison the associate cricket ranking system is a Stephen Hawking approved science of fairness.
Rankings are a joke.