Shrinking Family Size

As I was falling asleep the other night for some reason I wondered if I could detect a trend in smaller family size as the generations of my ancestors approached the present day. So, I undertook an analysis. I should note that these numbers are undoubtedly imprecise because there are certainly children of whom I have no record, for instance those who died in infancy and neither appeared in census records nor vital records.

Obviously, the statistics would be improved by increasing the sample size by including the other families in my tree and just noting how many generations removed from me they are. I don't pretend that this is in any way scientific.

Well, for what it's worth, here's what I found.

Grandparents:

information on 2/2

children: 3, 3

avg. 3

Great-Grandparents:

information on 4/4

children: 3, 5, 5, 6

avg. 4.75

GG-Grandparents:

information on 8/8

children: 2, 4, 4, 6, 6, 7, 7, 9

avg. 5.63

GGG-Grandparents:

information on 14/16

children: 2, 2, 4, 4, 4, 6, 7, 8, 8, 8, 8, 8, 10, 10

avg. 6.36

GGGG-Grandparents:

information on 11/32

children: 4, 5, 5, 6, 6, 7, 8, 9, 10, 11, 13

avg. 7.64

I found it interesting that each generation had approximately one more child than the previous one. I only wish I had more information on the missing gggg-grandparents. Maybe someday.