Utility meter cycles

Configuration
1

I want to use the utility meter with my Daily Rain rare of my WS2900 wheaterstation.
I see posible cycles of day, week, mont and year.
Does annyone know the posibility of more the one day?
Two or three days

2

Use the cron option, something like this 0 0 */3 * *

3

Cron instead of cycle?

4

Yes.