Common year starting on Monday

In the (currently used) Gregorian calendar, along with Sunday, Wednesday, Friday or Saturday, the fourteen types of year (seven common, seven leap) repeat in a 400-year cycle (20871 weeks). Forty-three common years per cycle or exactly 10.75% start on a Monday. The 28-year sub-cycle only spans across century years divisible by 400, e.g. 1600, 2000, and 2400.

400 year cycle (add any multiple of 400 to a number in the following list to get a year with this calendar.)

century 1: 1, 7, 18, 29, 35, 46, 57, 63, 74, 85, 91

century 2: 103, 114, 125, 131, 142, 153, 159, 170, 181, 187, 198

century 3: 210, 221, 227, 238, 249, 255, 266, 277, 283, 294, 300

century 4: 306, 317, 323, 334, 345, 351, 362, 373, 379, 390

In the Julian calendar, the fourteen types of year (seven common, seven leap) repeat in a 28-year cycle (1461 weeks). This sequence occurs exactly once within a cycle, and every common letter thrice.

As the Julian calendar repeats after 28 years that means it will also repeat after 700 years, i.e. 25 cycles. The year's position in the cycle is given by the formula ((year + 8) mod 28) + 1). Years 6, 12 and 23 of the cycle are common years beginning on Monday. 2017 is year 10 of the cycle. Approximately 10.71% of all years are common years beginning on Monday.