Ancestor Score Completeness Statistics - 2023

Geneanet defines the Ancestor Score as 

“comparing the number of possible ancestors with 

the number of identified ancestors on a 10-generation report”. 

Inspired by the Ancestor Score - or “Completeness Statistics” - of other blogs and GeneaNet's definition above, I generated my first one in February 2016. Since then I haven't just been able to linearly increase my known ancestors. Instead, I had to remove a whole line of wrong ancestors in 2018.

I could only partially replace them by already existing ancestors - due to inbreeding among my ancestors. Therefore, I decided to generate a new in-between ancestor score in August 2018 to be able to continue this series of posts (and removed the wrong one of 2017). Since then I've been gradually able to increase my number ancestors.

The generation with the most known ancestors is the 13th generation with just 20,8% of the theoretically maximum number of ancestors in that generation. In the 12th generation I've found 842 ancestors so far, and that's 41.1% of the theoretical maximum (without inbreeding).

At birth, the human sex-ratio differs; slightly more boys are born than girls. The ‘natural’ sex-ratio at birth is around 103-107 boys per 100 girls. There are biological reasons for this: boys are more susceptible to birth complications, and infectious diseases.
Genealogy is actually even more male-biased, because usually the males owned the properties, so males can sometimes be traced in property records, when church records are missing. Additionally, even in old records, males are sometimes mentioned with a surname, but females not even with a patronymic, rendering it impossible to find their parents. As a result, of my ancestors found in the 13th generation 43% is female, and 57% is male. In the 16th generation it's even worse with 63% males.

My ancestors mostly originate in the provinces of South Holland and North Brabant (mostly in the part that belonged to Holland before 1800) - with a recent increase in the number of ancestors in the province of Utrecht.

Composition and Bandwidth of various Generations
Gen	Composition										Bandwidth **
	Men	Women	Total	% 2023	% 2022	% 2021	% 2020	% 2019	% 2018*	% 2016	From	Until
G 3	2	2	4	100.0	100.0	100.0	100.0	100.0	100.0	100.0	1892	1906
G 4	4	4	8	100.0	100.0	100.0	100.0	100.0	100.0	100.0	1850	1880
G 5	8	8	16	100.0	100.0	100.0	100.0	100.0	100.0	100.0	1804	1857
G 6	16	16	32	100.0	100.0	100.0	100.0	100.0	100.0	100.0	1756	1832
G 7	30	30	60	93,8	93.8	93.8	93.8	93.8	93.8	93.8	1724	1802
G 8	59	59	118	92.2	92.2	92.2	92.2	92.2	92.2	90.6	1680	1777
G 9	114	113	227	88.7	88.7	88.7	89.1	89.1	88.3	86.7	1645	1749
G 10	207	202	409	79.9	79.9	79.7	79.7	79.5	78.7	76.4	1600	1722
G 11	344	316	660	64.5	64.4	62.4	61.8	61.2	60.8	57.0	1560	1695
G 12	452	390	842	41.1	41.0	39.0	38.4	37.6	37.3	33.8	1510	1666
G 13	484	368	852	20.8	20.6	19.0	18.7	18.1	17.9	15.7	1505	1645
G 14	442	308	750	9.2	9.0	7.6	7.3	7.0	7.1	6.1	1440	1625
G 15	331	217	548	3.3	3.2	2.5	2.3	2.0	2.0	1.6	1440	1580
G 16	202	119	321	1.0	1.0	0.7	0.6	0.6	0.6	0.5	1395	1540
G 17	109	54	163	0.3	0.2	0.2	0.2	0.2	0.2	0.1	1365	1500
G 18	64	32	96	0.1	0.1	0.1	0.1	0.1	0.1	0.0	1335	1470

     *) The years 2016, 2019 and 2020 feature an ancestor score of February, 2018 has an August score, 2021 and 2022 have a January score..
   **) The Bandwidth of a generation is determined by the earliest and latest known birth or baptism date within that generation.
  ***) I have many ancestors in places like Sint Anthoniepolder, 's-Gravendeel, Wieldrecht and Hendrik-Ido-Ambacht, where pre-1800 baptism records are (mostly) missing.

Further Reading: Geneanet's Ancestor Score Definition, Equivalent Complete Generations, Identical Ancestors Point, Coefficient Of Relationship, Gender Ration, Completeness Index.