Of course it can be simpler I didn’t know if Ioannis’ comment is sarcastic or not
It is very simple once you realise it’s incremented to overflow, so the number itself has no meaning.

Ok, mine is so old there’s no 40MHz definition in it!

it doesn’t hurt to see this number: 49992. It’s how many instructions you have after the timer interrupt
that will be free from further interrupt if you’re doing something on TicksChanged rather than SecondsChanged.
So I have learned to Read/Write I2C, Write LCD, etc in that time.

Next time I do any LED clock I’d like to try a centi and millisecond display HH:MM:SS:cc:mm!