New Orleans measures its Mardi Gras crowd population by the tonnage of trash left behind. 200 tons is a good year. Success is rated by the number of arrests, and how much money you made during this period, subtracted by what you have to pay out in cleanup, repairs (car, building, personal) and the cost of any upcoming court appearances you may or may not have to make.
bonboard adds a good writeup, and it's close enough to be accurate for our purposes, but to be really accurate, I'll add this bit I found on the web (edited):
The commonly stated rule, that Easter Day is the first Sunday after the full moon that occurs next after the vernal equinox, is somewhat misleading because it is not a precise statement of the actual ecclesiastical rules.
The actual conditions to determine the date for Easter are:
- Easter must be on a Sunday.
- This Sunday must follow the 14th day of the paschal moon.
- The paschal moon is that of which the 14th day (full moon) falls on or next follows the day of the vernal equinox.
- The equinox is fixed in the calendar as March 21. Easter can never occur before March 22 or later than April 25.
In order that the date for Easter be incontrovertibly fixed, and determinable indefinitely in advance, the Church constructed special tables for calculating the time of the paschal moon. There are three major differences to note between the ecclesiastical system and the astronomical system.
- The 14th day of the paschal moon is not necessarily identical to the time of astronomical full moon. The ecclesiastical tables do not account for the full complexity of the lunar motion.
- The vernal equinox has a precise astronomical definition determined by the actual motion of the Sun. It is the precise time at which the apparent longitude of the Sun is zero degrees. The actual date varies very slightly from year to year. In the ecclesiastical system the vernal equinox is fixed at March 21 regardless of the actual motion of the Sun.
- The date of Easter is a specific calendar date. Easter starts when that date starts for your time zone. Astronomical phenomena occurs at a specific date and time all over the Earth at once.
--from the Astronomical Applications Department, US Naval Observatory
It is therefore possible, from a technical standpoint, that different parts of the world may celebrate Easter in a different week, but when it comes to Mardi Gras, we're too drunk to care. We're too drunk to do laundry, go grocery shopping, eat, remember where we parked, think, or do anything but drool on our shoes and piss in an alley.