Missing payments. If you don't see a recent payment you've made, make sure you've allowed enough time for the payment to post to your account: Payments made by electronic check, by credit card, at a T-Mobile store, or over the phone usually post to your account right away, but it can take up to three hours.
Nothing in-game uses Kerbin days/years as far as I can tell. A day is defined as 86400 seconds, and a year as 365 days.
Sol: year= (365 days/year)/ (7 days/week) = 52.143 weeks/year; Here we have made the video for our users to get information easily as possible. Visit Education category to educate yourself more. How many Weeks are in a Year video