OK, not tested but try this.
var date MyDate = [your date field here];
var date SundayOfDateWeek = FirstDayOfWeek($MyDate);
var Date SundayOfToday = FirstDayOfWeek (Today());
IF(
$MyDate < Today(), "Past",
$SundayOfDateWeek = $SundayOfToday, "This Week",
$SundayOfDateWeek = $SundayOfToday, + Weeks(1), "Next Week",
$SundayOfDateWeek = $SundayOfToday, + Weeks(2), "Third Week Out",
$SundayOfDateWeek = $SundayOfToday, + Weeks(3), "Fourth Week Out",
$SundayOfDateWeek > $SundayOfToday, + Weeks(3), "4+ Weeks Out")
If you want this to be sorted you can add some extra spaces in front of the words tpo dorce the sort or else number them like "0. Past" or "1. This Week"
------------------------------
Mark Shnier (Your Quickbase Coach)
mark.shnier@gmail.com
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