1. My guess is that it was approximately 700 moons (a "moon" is kinda like a complete lunar phase, which takes roughly one month) before the main setting when Granny Smith founded Ponyville. This is where it starts off with 1 bit. 2. By the time Granny Smith was middle aged, it was probably about 300-350 moons before the main setting, and this is where inflation begins, where 1 bit from 700 moons ago would now be 2 bits. 3. Then comes the time where the Mane Six, especially Twilight, are just little fillies, which takes place approximately 100 moons before the main setting. By then, 1 bit from 700 moons ago inflates to about 5 bits. 4. Next after that is the main setting itself. Throughout this time, Twilight lives in Ponyville and hangs out with her best friends. In this setting, 1 bit from 700 moons ago is now 10 bits. 5. Finally, there's the future setting. It takes place about 250 moons after Twilight is crowned the new ruler of Equestria. By this time, 10 bits from the main setting inflates to about 15 bits.
Now, my theory may not be completely accurate, but what are your opinions about the inflation rates of the bits? Share them in the comments below.