I think that checking your word count is the shortest way to lowering your writing speed.
Maybe it was just my personal problem, but since switching to a different program that doesn't show the word count, I am doing fairly consistent 2k words a day. Compared to the time before, when I rarely did more than 1,5k in a day, that's a massive improvement.
Today I truly understood why some people write 10k words long chapters.
I wrote 7,3k words in a single chapter (not in one day, I'm not that far gone), still got a lot of things to say but it's high time I went to bed, and I've no idea how to divide it into smaller chunks without brutally cutting it apart and ruining the pacing.