The Levitt Calendar at a Glance

Year Published	1954
Days per Week	6-7
Days per Month	55-56
Months per Year	12
Base Year Length	668
Leap Days	1
Leap Day Position	end of year
Basic Intercalation Formula	2x668 + 3x669
Extended Intercalation Formula (\ denotes integer division)	Y\5 + (Y-2)\5 + (Y-3)\5 - Y\1000
Mean Length of Calendar Year	668.599
Base Astronomical Year	Mean Tropical
Accuracy	145 years
Cycle of Perpetuity	56 days
Mean L_S of Beginning of Year	58.3
Year Count Start	1
Epoch (CE)	-4712 Jan 1
Epoch (JD)	0

Notes:

Each month begins on the first day of the week. The week at the end of each quarter contains only six days.
This is one of several Symmetric Gregorian Martian calendars, which generally have the following characteristics:
- Divide the Martian year into 12 months of approximately equal duration.
- Retain the seven-day week.
- Begin the year near the Winter solstice
- Place the leap day(s) in the second month.
- Base the month names on the traditional Roman names
Other types of 12-month calendars are:

	It's About Time I. M. Levitt
	Mars Clock and Calendar I. M. Levitt
	Calendar
	Martian Time
	Martian Time Survey 2.2