90% of Muslims are Sunni and heretics according to the 9% Shiite.Who are there more of ,Shiite or Sunni ?
The remaining 1% are allawite or Salifi or other sub sects.
Shia are concentrated in the old Persian boundaries (Iran, parts of Iraq, but there are also 30 million Shia in pakistan which will lead to a major religious war along sect lines at some point).
The Sunni appear to be the vast majority but the fact is most Sunni eg the ones in india, south east Asia, Africa etc or non Arabic are not considered 'real Muslims' by Arab Sunni.
They are only Sunni by accident or imposition (via Mongol then Mughal empire top down dictates) so the true cornerstone of Arab sunni.
However of those 90% sunni, about 60% do not lead a faithful or true Islamic lifestyle -and 70% are not Arab so according to the Arab Sunni there is a subdivision with Sunni also as to being Arab or not, then being a true believer or not.