How many months are in a runescape year and how many days are in the year and each month? How many years is a runescape "age"? Asking for the canon time amount. And the rune clock in the poh doesn't even change.
The 'ages' all vary in length, though the first four appear to follow a pattern. The first age was approximately 4000 years long, the second age 2000 years, the third age 4000 years, the fourth age 2000 years, and the fifth age only 169 years.