Fact: Each year is 365 days long. There are 12 months in a year. Pill packs are filled for 4 x 7 = 28 days. 28 x 13 is 364. So each year 13 pill packs are filled but only 12 monthly statements sent, so in one of those months each year you will get a double portion to make up for the extra pill pack (13 packs vs 12 times per year).
We hope this explanation helps you understand the financial situation. If you currently pay a certain amount for each pill pack, say $50 for each, be aware that each month you are only being billed 1/13th of the annual amount not 1/12th. Or another way to think of it, 11 out of 12 months you are only being billed for 1/13th of the expected annual amount or about 10% less than the actual average monthly amount. One of those months will be 2/13th of the expected annual amount. In the case above, paying $54.17/mo would pay the 13 packs off in the year: i.e.13x$50=$650 and $54.17x12=$650.04
Also, every 28 years you technically would get an extra charge to make up for another pill pack .. the extra day ((365- 364) x 28 times) .. but I doubt you will notice ..
Further confusions:
- https://en.wikipedia.org/wiki/International_Fixed_Calendar The International Fixed Calendar or the Equal Month calendar is a solar calendar proposal for calendar reform designed by Moses B. Cotsworth (1902). It divides the solar year into 13 months of 28 days each.
- https://en.wikipedia.org/wiki/Calendar_reform Historical calendar reform tidbits: eg 46 BC was 445 days long under Julius Ceaser.
- My own proposal for a metric year of 10 months per year is unlikely to get much interest ..