- the following is from my new repo about r and r studio tips and tricks
interval(ymd_hms("2019-01-04 18:40:00", tz = "America/Vancouver"), ymd_hms("2019-01-07 12:59:00", tz = "America/Vancouver")) / hours(1)  66.31667
- The above ^^^^ is the most accurate and the best way to compute daynumber starting at an arbitrary day of the week e.g. Tuesday for Firefox releases!
You can also use lubridate
durations, but durations aren't accurate when you transition from month to month or year to year