Who started punctuating like a language model?

Em dashes per post counts what a reader meets in one sitting, but it moves when posts get longer as well as when punctuation changes, and across this chart the average post grew 2.0×, from about 540 words in 2014 to 1,059 today. Over the same span the rate per 1,000 words went down 4%. Most of the climb above is longer posts, not denser punctuation. Switch to per 1,000 words to take length out of it.

Other things that changed

A rise in one punctuation mark is thin evidence on its own. These are three other ways the prose moved over the same period. Sentence variation is the closest thing here to whether something reads like a person: human writing is bursty, a short sentence next to a long one, and a falling line means sentences are converging on one length.Marker words counts a narrow set that was rare in this corpus before 2023 — delve, tapestry, myriad, intricate and a few dozen others. None of these detects anything. Together they show whether a blog's writing changed shape, not who wrote it.

The ranking

Ordered by em dashes per 1,000 words since 2024. Rates divide summed dashes by summed words over the window, so a prolific month counts for more than a quiet one. Blogs with fewer than 40 usable posts are left out; Method lists them and why.