And What I Think About It...
I thought I was well informed about the proper use of the apostrophe, but I visited a webpage about apostrophes tonight and found a rule that surprised me.
Another common error is using an apostrophe to indicate a plural number set. "The low temperature will be in the 40's" is incorrect. There should be no apostrophe in 40s. Similarly, decades should not have apostrophes unless they are possessing something.
Source: How to Use Apostrophes -WikiHow
I investigated further and found similar information:
Years in a decade are often marked with an s only: the 1930s, the '70s.
Source: Uses of the Apostrophe
It is no longer considered necessary or even correct to create the plural of years or decades or abbreviations with an apostrophe:
-He wrote several novels during the 1930s.
Source: Google Answers: Grammar--Plural of Abbreviation
I'm positive that back in the Dark Ages, I was taught to add an apostrophe before the -s. when writing the plural of a number. And the last two quotes above do hint that an apostrophe in the plural of numbers was once acceptable. I found two examples in reference books that suggest this, also.
The Little, Brown Handbook (by H. Ramsey Fowler and Jane E. Aaron, published by HarperCollins Publishers Inc., New York, 1992, p. 425) says that letters, numbers, and words can be made plural by italicizing (or underlining) and then adding an apostrophe plus -s. But the following is added:
Exception: References to the years in a decade are not underlined and often omit the apostrophe. Thus either 1960's or 1960s in acceptable as long as usage is consistent.
From a 1977 edition of The Gregg Reference Manual (by William A. Sabin, published by McGraw-Hill, Inc., New York, 1977, p. 125-126.)
Numbers expressed in figures are pluralized by the addition of s alone.
in the 1980s
temperature in the 40s
sort these 1040s and W-2s
NOTE: Some authorities still sanction the use of an apostrophe before the s. However the apostrophe is functionally unnecessary except where confusion might otherwise result.
Well, I can change. I'll give up the apostrophe in the plurals of numbers. When I see a number plural that's written the old-fashioned, incorrect way in the blog archives, I'll edit it. I do want to use proper punctuation.
I draw the line on my efforts to be correct, though. I'm not going to do proper footnotes. This is only a blog, not a research paper. I'll include the information about the darned book, and if you want a proper footnote, go ahead and write one.