For now, you can use various tools online to calculate your ingame time.

I am writing this guide for the following site:

https://www.timeanddate.com/date/duration.html

Add your start date and end date like so:

Make sure to keep the box "Include end date in calculation" unchecked (since our starting date is technically Day 0)

Then just click calculate.

The end result will give you the exact amount in the format you need:

22 years, 9 months, 12 days