The Aitken Calendar at a Glance

Year Published	1936
Days per Week	7
Days per Month	41-42
Months per Year	16
Base Year Length	Option 1: 667 Option 2: 668 Option 3: 668
Leap Days	Option 1: 2 Option 2: 3 Option 3: 1, 2
Leap Day Position	Option 1: undefined Option 2: undefined Option 3: mid-year + end of year
Basic Intercalation Formula	Option 1: 1x667 + 4x669 Option 2: 4x668 + 1x671 Option 3: 5x668 + 4x669 + 1x670
Extended Intercalation Formula (\ denotes integer division)	Option 1: -2 * (Y\5) Option 2: 3 * (Y\5) Option 3: Y\2 + Y\10
Mean Length of Calendar Year	668.6
Base Astronomical Year	Vernal Equinox
Accuracy	106 years
Cycle of Perpetuity	Option 1: undefined Option 2: undefined Option 3: 2 years
Mean L_S of Beginning of Year	0.0
Year Count Start	undefined
Epoch (CE)	undefined
Epoch (JD)	undefined

Notes:

Option 3 is the mst detailed proposal and is the preferred option.
The relationship between the days of the week and the months repeats over a biennial cycle. Even-numbered years begin on the first sol of the week. The months within each quarter begin on the first day of the week.
This is one of several 16-month calendars.

	Time Measures on Mars Robert G. Aitken
	Calendar for Mars Robert S. Richardson
	Calendar
	Martian Time
	Martian Time Survey 2.2