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News Gram™ December 2006

December 2006 ~ Volume 13, No. 5

As the year winds toward its inevitable end, as people celebrate Christmas, Kwanzaa and Chanukah, and as the New Year looms larger each day, we might stop for a moment and ask how the year descended on us all. By the year we mean that period of time during which the four seasons have their repetitive tenure, the tides go through their motions with predictable results and the days lengthen and shorten with the movement of the sun above. Each year we experience the movements, shadows, rains and stars that define how far we have progressed from beginning to end.

That humans require a calendar of one or another sort to help organize their lives becomes apparent when we look at the wide variety of systems to divide up the year. Over the centuries, different systems have been introduced to mark the days of our lives:

Solar Calendars: These assign a date to each day in which the sun goes through its cycle. It may be measured by the interval of time between sunrise and sunset (with night intervening) or between two successive risings or settings of the sun. Such a calendar has days of different lengths, a commonly recognized feature, since we observe longer days in summer and shorter ones in winter. An alternative system employs something called the mean solar day the length of which is 24 hours year round. Typically, a solar calendar has 365 days, the most famous of which are the Gregorian and Julian calendars. The latter has 365 days apportioned among 12 months. It requires a leap day every fourth year to make up for its exact length of 365.25 days. This system, introduced by Julius Caesar in 45 BCE, was revised by Pope Gregory XIII in 1582.

This new system was first adopted by Catholic countries. Protestant states followed the next year. Russia refused to hop on board, and when they underwent a revolution in 1917, it relinquished its recalcitrant hold on the Julian system and adopted its own model. Interestingly, the so-called October Revolution, when measured according to the Gregorian calendar, occurred in November. Go figure.

Lunar Calendars: This system uses the lunar phase cycle, one month being the time for the moon to go through all its phases. There is an arithmetic quirk about the lunar calendar in that the length of the lunar cycle does not divide evenly into the length of a tropical year, the result being that seasonal drift so that the time for sewing and that for reaping occur at progressively different times of each succeeding year. However, as one might guess, the lunar calendar stays constant with the schedule of tides, which fishermen and others engaged in maritime activities find helpful.

To compensate for apparently drifting seasons, the lunisolar calendar evolved. It functions by adding an extra month to the calendar periodically to realign the seasons. For instance, the Jewish calendar has a 19-year cycle of 235 lunar months which adds an additional month every two or three years. This system is akin to the Chinese calendar that is still used to mark traditional Chinese holidays. At other times, the Chinese employ the Gregorian calendar.

Fiscal Calendars: These are designed for such prosaic purposes as tax schedules, levels of commercial activity and year-end planning. In the United States, the fiscal year corresponds to the calendar year (January through December), though there is no stipulation that the length be exactly one year. Its length extends from New Year’s Day of the calendar system in effect to the day before the next New Year’s Day. Sometimes, businesses will arrange their own fiscal years so that they don’t correspond with the calendar year because there may be heavy business activity at the same time as annual reports come due. In this instance, we find an interaction of sorts between the factors generating the need for a fiscal calendar and those behind the calendar year, be it Gregorian, Julian, Jewish or other.

While you’re trying to figure all this out, please accept our wishes for a beautiful holiday season and a happy, healthy New Year!

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