At the end of each month, I use the DNAGedcom client to download my matches from Ancestry, as well as those of my father, my mother and (one of) my sibling(s).
Here are our 4th cousin level (generally, 20.0 cM or more total DNA shared) and our total match counts as of December 30, 2018. My dad has nearly twice as many total matches as my mom, likely because of his 100% Ireland/British Isles ancestry, while mom’s father, a 1st-generation American hails from the Marche region of Italy. Not much DNA testing going on with that side of her family.
Notice, however, that even though my mom’s total matches is roughly half that of dad’s, she has almost as many 4th cousin level matches as he does.
Let’s take a look at a few of the numbers, percentage-wise. You can see that my dad and my sibling are tracking at the same ratio of 4th cousin level matches to total matches. My percentage is a bit smaller, but mom’s 4th cousins are just over 3% of her total matches.
I suspect the reason for Mom’s higher percentage of 4th cousin matches is due to the fact that she has 4 great-great grandparents whose ancestors have been in the United States since the 18th century. Dad, on the other hand, has only 2 great-great grandparents who have been in the U.S. since the 18th century.
How fast have the numbers grown over the years? It will vary for each person who does a DNA test with Ancestry. In general, if you are of European heritage, and you have many colonial ancestors, you will have a lot of matches, and a lot of matches at the 4th cousin level or closer. On the other hand, if you have ancestors that immigrated to the U.S. in the 20th century (as I do, and my mom does), you’ll have proportionately fewer matches.
That said, the number of my matches increases daily! I’ve been averaging more than 17 new matches per day in the last 3 years. My dad (not shown here) is averaging over 31 new matches per day in the last 3 years. I suspect those with extended colonial roots have an even greater number of matches coming in, as more and more people test.
Have you taken a recent look at your match totals?