Interesting Thread....
OK, from my personal perspective....
I am Third Generation, My grandparents were witnesses in the 1940's.... so from this couple what do we have.... They had Four Children, all left, two came back. Of these four... 2/4 = 50% staying.
1/ My Parent, Left, married out of the 'truth', spouse came into 'truth', had three children of whom only one has stayed. 1/3 = 33% staying.
2/ Sibling #1, Married in 'truth', had two children, entire family left in late 1960's. 0/2 = 0%
3/ Sibling #2, Left already accounted for.
4/ Sibling #3, Left, married out of 'truth', returned, had three children, spouse came into 'truth'. One stayed, one left, one DF. 1/3 = 30%
So in total from this one JW couple, including spouses upto the second generation we have the following:-
In Out %
2 Grandparents 2 0 100
4 2nd Gen Children 2 2 50
4 2nd Gen Spouses 2 2 50
6 Grandchildren (raised in) 2 4 33
Total 8 8 50
This does not account for 4 Grandchildren raised outside, or take account of the 4th Generation, who are getting to the decision age.
Perhaps we should run a survey...?