The religious tradition of 18 to 30 years across the last five decades.

Evangelical: 20% to 20% (No change)
Mainline: 21% to 5% (Down 15%)
Black Protestant: 10% to 7% (Down 3%)
Catholic: 30% to 25% (Down 5%)
Other Faith: 6% to 9% (Up 3%)
None: 12% to 33% (Up 21%)

It's just stunning how very young mainline Protestants there are now.

Consider this:

For every mainline Protestant under the age of 30 in the 2010s, there are:

4 evangelicals
5 Catholics
2 people of other faith
6 nones

This is just the white, non-Hispanic sample.

Evangelicals: 23% to 23% (no change)
Mainline: 24% to 7% (17 pt. decline)
Catholic: 33% to 26% (7 pt. decline)
Other Faith: 6% to 9% (3 pt. increase)
Nones: 13% to 36% (23 pt. increase)