Hold the goodbyes. The decade of Reagan and AIDS and Madonna is not over yet. In fact, the decade in which we have been living for the past few years will not end, strictly speaking, until midnight Dec. 31, 1990.
This may seem counter-intuitive, especially since we are now obviously in the 1990s. But a year ending in zero is actually the 10th and final year of the old decade, not the first year of the new.Take the year 2000. As calendar purists have been arguing for years, it has to be the end of the 20th century, not the beginning of the 21st. After all, simple arithmetic shows it takes 2,000 years to make 20 centuries. Thus the 21st century will not start until the year 2001.
Or consider the question from the other end of the calendar.
The first year of the current system of numbering years did not begin on Jan. 1 of the year 0. The first year was, of course, 1, which means that on Dec. 31, 9, our ancestors did not set off firecrackers and reminisce about the first decade A.D. because that decade was only nine years old.
So is ours.