What is the Hanke-Henry Permanent Calendar?
The Hanke-Henry Permanent Calendar (HHPC) would be the same year after year. For example, July 4 would always fall on a Wednesday; Tax Day—April 15—would always fall on a Sunday, and so forth. The HHPC is made up of four 91-day quarters, each comprised of three months – for a total of 364 days every year. But, the number of days in a full orbit of the Earth around the sun is approximately 365.24. So, to keep the HHPC synchronized with the astronomical year, we would add 7 days at the end of December every five years. All calendars have to deal with this so-called calendar drift problem one way or another. That’s why our familiar Gregorian calendar, which Pope Gregory XIII introduced in 1582, has to have a leap year thrown in ever four years. If the drift wasn’t corrected for, we would eventually be celebrating Christmas during the summer season.Let’s just think of the HHPC extra week as a week of paid vacation and move on.
So you’re the titular Hanke, who’s the titular Henry?
Richard Conn Henry, a professor of physics and astronomy at Hopkins and I developed the HHPC. We have been assisted by Hopkins students studying applied mathematics, economics, international relations and physics. The last time this specific type of interdisciplinary research took place at Hopkins was in the 19th century, when the great Simon Newcomb, a renowned astronomer and economist, grappled with these issues on his own.
What are the benefits of this calendar system?
Planning and scheduling for work, school, sporting events, holidays, and so forth could be done once and for always. Scheduling committees would become obsolete, and the time saved would be an enormous benefit. The HHPC would make civil holiday scheduling much easier. For example, these holidays could be targeted for Fridays and Mondays, rather than during the middle of the week. European studies estimate that the benefits from putting a more rational order to civil holidays could be at least 1% of GDP. Applying this percent to the U.S., we are talking about very big money—$160 billion annually.
Financial calculations would also be simplified. To determine how much interest accrues for bonds, mortgages, swaps, etc., day counts are required. The current calendar contains complexities and anomalies that create day-count problems and generate significant errors. The worldwide benefits would be huge—perhaps as much $130 billion annually.
What are some possible problems? For instance, what happens if you were born on January 31, a day that will no longer exist because January will have 30 days?
Most of the so-called problems are, in a sense, trivial. What if you were born on January 31? You would, of course, keep the birth date of January 31, on a Gregorian calendar. But, for the purposes of celebrating the blessed event you would be able to choose any date you wished on the HHPC. That is in effect, what Queen Elizabeth II does now. The Queen's birth date is April 21. But, the date on which her birthday is celebrated around the Commonwealth varies, falling between the end of May and the start of June. The Royals don't leave anything to chance. They have calibrated the birthday celebrations to coincide with a high probability of good weather.
It should be noted that the current calendar we use in the U.S. contains exactly this kind of so-called problem. When do you celebrate your birthday, if you were born in a leap year, on February 29? Well, you are called a “leaper” and you pick a day to celebrate your birthday in non-leap years – usually February 28 or March 1.
So how would this be implemented?
In the past, new calendars have been mandated by emperors, like Julius Caesar or ecclesiastical authorities, like Pope Gregory XIII. Today, we have social media. If the HHPC goes viral, that might just do the trick and break the grip of a second-rate calendar imposed by a Pope over 400 years ago.