Speed depends on the writer, how intricate the story is, how much research is involved in it, and many other factors.
When I did NaNoWriMo last year, I averaged about 2700 words per day for 22 days to complete the project.
My profile has a bar graph with the word total at the end of each day. To accomplish that, I had the story outlined so that I knew what would happen in each chapter, hence saving myself the loss of time thinking, "Okay, what am I going to do next?"
Some stories flounder for a while. The one I just finished,
Merrowsong, was first started a couple of years ago. I wrote maybe a chapter, and then it sat until something caused it to click again. The drawback to that is I have some inconsistencies from that first chapter through the rest of the story that will have to be corrected in the revision process, but the first draft is done. That's the tough part.
So far, I have never gotten sick of one of my stories. I'm not sure how I've managed that. I've gone over
Cardan's Pod a bunch of times, and I still love the characters and the story.
One option you might try for your word count is to keep two separate files. In one, just have the text of the story. In the other, copy the text and add your notes. That way, you have a "clean" copy if you want someone to read over it and critique it, plus you can use your tools such as word count, "find and replace", etc.
“It is the artist who realizes that there is a supreme force above him and works gladly away as a small apprentice under God's heaven.” ~ Alexandr Solzhenitsyn