Well, it took a little over 30 minutes, but I used a calculator to calculate my words read (adding the words for all the stories in my favorites list). It will be a little off because 1) not all of the stories I've read are favorited, and 2) I included FoE and FoE: PH.
[Adventure] Celestia and Luna were born as earth pony foals in a dangerous world. They must rise from nothing to become the princess we know, upsetting chiefs, gods, and the very forces of nature in the balance. 112217