According to the new index, the United States has a moderate level of religious diversity, ranking 68th among the 232 countries and territories included in the study. Counting both adults and children, Christians constitute a sizable majority of the 2010 U.S. population (78%). Of the seven other major religious groups, only the religiously unaffiliated claim a substantial share of the U.S. population (16%). All other religious groups combined account for about 5% of Americans. (The U.S. would register as considerably more diverse if subgroups within Christianity were counted.)

Here is a map from Korean research:

Pew research USA:

I just live by : Do unto others as you would have them do unto you.