Holdun Consistent Calendar
W H A T

Abbreviations used in text:
TC - Traditional Calendar (Sunday first day of week version)
HCC - Holdun Consistent Calendar

The Purpose of the HCC
The purpose of the HCC is, in large part, to bring a consistency in the number of days in a given month, avoiding the "Thirty days has November, April , June, and November. All the rest have 31, except for February, which has 28, unless the year is divisible by 4 - but not 100 unless it is also divisible by 400, - in which case it has 29, unless it is also divisible by 4000 which, pending adoption, should only have 28." zaniness. Visit the Why page for more specific reasons why the HCC is a worthwhile calendar to use in many situations. Of course, even if there is a significant adoption of the HCC the TC will of course not go away. It is far too embedded in modern civilization despite it drawbacks. The HCC is meant to be a logical alternative to the TC in certain use cases such as in business accounting and work scheduling. So it's not an either HCC or TC. It's HCC and TC where the HCC simple structure is appreciated and advantageous. There is a modern precedent for this dual calendar usage in the Arab world which uses a Muslim calendar for largely religious date keeping, and a Gregorian calendar for largely secular usage.

The Big Picture
Rather than creating a completely new and improved framework for time keeping from scratch, the HCC adopts much of the tradicional calendar, TC for short, as a foundation thus minimizing differences between the HCC and the TC, each minute has 60 seconds, each hour 60 minutes, each day is 24 hours. The HCC retains the traditional twelve month year - January through December - as in the TC format. Summer will always be in July, winter in January.

Week Starts on Monday
In the HCC there are four seven day weeks to each month of 28 days. The HCC uses the same seven days per week with the same names for the days as in TC. But in the HCC each week begins on a Monday as per ISO 8601, the international standard for the representation of dates and times.
< br /> If there is interest, other versions of the TC can be presented besides the Sunday start of the week for the United States, Canada, much of South America and others shown in this version; there could be a Monday start of the TC week for European and like-minded nations. Or a Saturday start of the TC week where that is common in the Muslim world. Contact us if that is of interest to you.)

But for consistency and simplicity, the first day of the week in the HCC is Monday wherever it is used.

Month Starts on Monday
In the TC there is no attempt to begin a month on the first day of a week. The first day of a TC month could be on any day of the week. Many use cases will find it very convenient to start every new month on the first day of the first week as in the HCC.

Quarters Starts on Monday
Institutions and businesses that use quarters of a year for reporting (think any company that is on a major stock exchange) are an important use case for HCC. As with the starting day of a given month or year, in the TC there is no attempt to begin a quarter on the first day of a week. The first day of a TC quarter could be on any day of the week. Many use cases will find it very convenient to start every new quarter on the first day of the first week as in the HCC. See the Why page for more details as to why the HCC is better and more accurate for such reporting.

Year Starts on Monday
As with the starting day of a given month, in the TC there is no attempt to start a year on the first day of a week. The first day of a TC year could be on any day of the week. Again, many use cases will find it convenient to start every new year on the first day of the first week as in the HCC.

Weeks in a Month or Year
If you need to make weekly reports for a given month or year there are a couple of issues with using the HCC. One is that an HCC month or year, not being divisible by seven (except non-leap year February), more often than not the first week of a month or year bleeds over into the previous month or year, while the last week bleeds over into the following month or year. Do you think every year has 52 weeks? Not so fast my friend. (click bait alert!) See the Why page for the story of the 53 week year.

Time Zones
Time Zones don't exist in the HCC structure. This feature could be considered as consolation for the fact that 24 hours in the HCC does not follow as closely as 24 hours in the TC to the solar (sidereal) year (360 degree rotation) day by design. The TC day is 4 min over the solar year, while 24 hours in the HCC is 155 min under the solar year. The focus of the HCC is to be a yearly calendar simply and perfectly tracking the rotation of the earth around the sun. The TC, on the other hand, is a less than perfect tracker of the rotation of the Earth within an almost but not quite accurate tracker of the rotation of the Earth around the Sun by means of the duct tape and bailing wire of scattered leap years though the centuries.

Since the HCC day does not follow the solar year, it need not concern itself with attempts to keep, for example, the sun reaching its zenith around noon everywhere around the globe by use of switching time zones. Time zones are great for scheduling to get up at 7 A.M for an early morning breakfast anywhere you happen to be traveling. But not incorporating time zones into the HCC avoids much confusion when coordinating current or scheduling time across multiple jurisdictions around the globe. And even more so when calculating differences in shipping and traveling time between one or more areas that may or may not be in a different time zone, or scheduling a meeting with participants scattered across the world. Here again I will defer to Google or Wikipedia for the litany of details and complications in the use of time zones with the TC for anyone so inclined to explore this topic.

Here again we see an example where some use cases are best in the hands of the TC calendar/clock, whereas many others are best in the hands of the HCC calendar/clock. Choose the correct tool for the job at hand.

336 Days in a Year of Roughly Same Length as a TC
In the TC days are added in certain months (as in the "Thirty days..." ditty) to squeeze 365 days into roughly 75% of the years, while tossing in an extra day into the year roughly 25% of the time to reach 366 days. This scheme in a attempt to approximately match the 365.2425 days in an average year (over a 400 year period) It is interesting to note that a calendar that only used the add a leap year every four years rule - the Julian Calendar, with 365.25 days in an average year, - needed to be replaced in 1582 by the Gregorian Calendar (and ten days disappeared from existence in the process) as the three added leap year days in years divisible by 100 but not 400, over the centuries, forced the Spring Equinox to appear, by then, ten days earlier than indicated by the calendar. And that in turn upset the date for the celebration date of Easter which was a big deal back then. Anyway the Gregorian calendar with 365.2425 days per average year is the TC calendar we are dealing with here. Google or Wikipedia "Gregorian Calendar" for a much better explanation than I offered here.

But the TC is still a bit off where it needs to be. The solar year (one trip around the sun) takes 365.2422 days on average. This is where the proposed not adding a leap year if the year is evenly divisible by 4,000 comes into play. This brings the average day to the desired value. (Though still a little bit off - 315 569 26.08 seconds vs the actual solar year value of 315 569 25.22).

But from the get go the HCC year is exactly the length of a solar year!

The bottom line on the length of the HCC year vs the TC year is that in non-leap years the TC is (365.2422 - 365 = ) 0.2422 days behind the solar year it wishes to follow - somewhat less than six hours. In leap years the TC is (366 - 365.2422 = ) 0.7578 days ahead of the solar year - somewhat more than 18 hours. Meanwhile, year in and year out, without any "if divisible by 4/100/400/4000 then..." manipulations, the HCC exactly matches the length of one solar year. And within a simple framework of 336 days. To see the details of how this happens in the HCC, visit the How page.

An aside to 336 days in a year
The 365/366 day of the TC calendar cannot be broken into equal chunks of days applicable to both leap years and non-leap years. Thus the problem with 52/53 week years, months of 28/29/30/31 days, and quarters of 90/91/92 days.

On the HCC side of the ledger, 336 is evenly divisible by: 2,3,4,6,7(week),8,12,14,16,21,24,28(month),42,48,56,84(quarter),112,168.

So there is enormous flexibility in breaking the HCC year into consistent equal chunks of days should that prove advantageous.

Trade-offs
Of course there are trade-offs in moving away from the ubiquitous TC format. These trade-offs are such that adopters of the HCC, will regularly refer to a TC calendar for scheduled events such as birthdays or anniversaries, events that are outside specific HCC use cases such as accounting. But there is a TC->HCC Converter from a TC date to HCC date, and an HCC->TC Converter from an HCC date to a TC date, if either of those is wanted. Click the links above or in the menu to visit those.

Alternatively some might choose to use only the HCC. But back to trade-offs, similar to the dilema of people today who have birthdays or anniversaries on February 29th in the TC, and need to decide what day to celebrate the event in non-leap years, celebrating some birthdays or anniversaries, such as those occurring on November 30 TC, could be moved to November 28th or December 1st HCC. Alternatively, the HCC date for any event since 1583 (the first full year of the Gregorian Calendar) could be gotten from the HCC->TC Converter

And while a year in each calendar roughly begins and ends the same time, the months, weeks, and days within that year move at a more leisurely pace in the HCC, as it has to fit roughly the same amount of time in about 4 fewer weeks; and to fit each month into 28 days, not the 29, 30, or 31 that you know so well in the TC. This means that for most given dates and times, the two formats will look very different. As discussed above, sunrise or noon or sunset, from one day to the next, will be significantly less similar in hours, minutes in the HCC compared to the TC. Visit the How page for details on How that all works.