Religiously unaffiliated means they do not attend a church at all. A lot of people who are asked what their affiliation is just put whatever their parents were

Religiously unaffiliated means they do not attend a church at all. A lot of people who are asked what their affiliation is just put whatever their parents were or what they grew up in, even if now fully lapsed. Churches have attendance statistics that put religious affiliation in the 5-6% range(Varies with the religion and area, Muslims the highest, but also the most rapidly declining as the youth in the USA/Canada are free to depart)