An Ahnentafel (German ‘ancestor board’) table assigns a unique number to each person.
On your own Ahnentafel chart you are number 1. In the previous generation your father is 2 and your mother is 3. Your father’s number is calculated by doubling yours; your mother’s number is one plus double yours.
This scheme continues up the generations. Your paternal grandparents are 4 and 5. Your maternal grandparents are 6 and 7. Men have even numbers; women odd.
My table starts with my children as number 1 and incorporates both my husband Greg’s forebears and mine.
I use Ahnentafel numbering to keep track of our Most Recent Common Ancestors (MRCA), ancestors we share with our DNA matches, provided, of course, that I have been able to establish what the genealogical relationship is.
The update of my Ahnentafel index made me think about our progress on the tree. The last time I reviewed our tree progress was March 2020. At 31 March 2020 my tree showed 344 of the possible 1023 forebears up to 10 generations of 7th great grandparents. I know all 32 of my children’s 3rd great grandparents and thus all 62 of their possible ancestors to that level. At the 4th great grandparent level I know 53 of their 64 possible 4th great grandparents.
In the four months since March I haven’t made any progress in identifying more ancestors in these 10 generations, but I have made a little progress in the generations beyond, with two more 8th great grandparents, four 9th great grandparents, two 10th great grandparents, and two 11th great grandparents. Adam and Eve are coming up.
|Generation||Ancestors identified||Tree completeness at this level|
|Parents||2 of 2||100%|
|Grandparents||4 of 4||100%|
|Great-Grandparents||8 of 8||100%|
|2nd-Great-Grandparents||16 of 16||100%|
|3rd-Great-Grandparents||32 of 32||100%|
|4th-Great-Grandparents||53 of 64||83%|
|5th-Great-Grandparents||72 of 128||56%|
|6th-Great-Grandparents||76 of 256||30%|
|7th-Great-Grandparents||80 of 512||16%|
|8th-Great-Grandparents||66 of 1024||6.45%|
|9th-Great-Grandparents||43 of 2048||2.10%|
|10th-Great-Grandparents||31 of 4096||0.76%|
|11th-Great-Grandparents||21 of 8192||0.26%|
|12th-Great-Grandparents||12 of 16384||0.07%|
There is limited pedigree collapse: 10 people appear twice as our children’s 3rd great grandparents John Way and Sarah Daw were cousins who married.
Our family tree, including indirect relatives, has grown from 10,481 people in March 2020 to 10,928 as at August 2020. It now has 17,204 records (previously 16,099), 2,238 images (previously 2,109), and 305 stories (previously 289). I have added 65 posts.
These statistics give me a quick measure of the progress I’ve made. There still a long way to go…