This is fuzzy demand. What would you conclude Quranically if 90 percent Muslims offer Namaz (prayer), or mere 5 percent. Generally most Namaz is reduced to psychological means of feel better in the self eye of beholder, without scant regard to God wishes placed upon Muslims.
There are also sectarian monarchies that decide who a Muslim is, and who is not. Each sect is deviant to others. Aggregating population under each monarchy calling others Kafir, almost all Muslims theoretically would be kafir and so their prayers. The question could only be viewed better within Quranic perspective rather than collecting data.