I am sorry, but I do not accept your extrapolation
the·ism (thzm)
n.
Belief in the existence of a god or gods, especially belief in a personal God as creator and ruler of the world.
Paganism
Disparaging and Offensive. pertaining to the worship or worshipers of any religion that is neither Christian, Jewish, nor Muslim.
of, pertaining to, or characteristic of pagans.
Theism is the belief in God. The belief in anything other than God is not theism.
The column that contains those "Who believe in God" is for Christians, Moslems, Jews and Buddhists. The second column contains those "Who don't believe in God, but do Believe in a universal spirit or higher power" which is for beliefs like Paganism. They are not theists. If they were meant to be together than they would have been put together. One section believes in God, the other section does not. You cannot add them together just to make your point right. It does not work like that, and I am sure you know that. But let me just remind you of what you said.
Even if you add both figures together it is still not a "High" percentage.