Most of the time when you’re talking about decades, for example, the 1980s, 1970s or 1960s etc, you should not place an apostrophe before the ‘s’. Lots of people do, but have the courage of your convictions and refrain. Just say no.
The following are correct (all without an apostrophe):
“Patti Smith lived in New York in the late 1960s and early 1970s.”
“The 1960s saw many changes in society.”
“Shirts with big collars were popular in the 1970s.”
“In the 1950s, women were expected to stay at home.”
If you need some basic information about the possessive apostrophe, go to: The possessive apostrophe. Part 1: the basics.
The apostrophe and initialisms
The apostrophe and irregular plural nouns (e.g. ‘children’s toys’)
Wordwatch Towers 
Hi, Aky!
Welcome to the Unhealthily Obsessed With Apostrophes Club. You will soon experience an overwhelming urge to go around correcting public notices with a black marker pen; don’t worry, this is perfectly normal and medication is available.
It’s an interesting topic. I’ve been looking at a few style books and opinions vary as to how to refer to decades. However, all the authorities agree that an apostrophe should not be used before the “s”.
All of the following, for example, are correct:
1960s
60s
sixties
’60s (This example that you cite from Collins uses an apostrophe to denote that “19” has been omitted.)
Here’s the Guardian‘s rule on decades (it obviously doesn’t like decades being written out, as in “sixties”):
1950s, etc; use figures if you abbreviate: roaring 20s, swinging 60s, a woman in her 70s, the first reader’s email of the 00s (pronounced, unfortunately, “noughties”)
Don’t mix and match between, for example, “’60s” and “60s” in your writing: be consistent (and follow any housestyle you’re subject to).
By the way, I think “00s” looks very strange, but I’m not sure what the alternative would be.
Interestingly, The Times’ style guide specifies “the Sixties” with the decade capitalised. I don’t like that at all.
Thanks for raising all this! I haven’t thought about it for a while. As previously mentioned, feel free to ask about anything that’s puzzling you.
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Today, I purchased a Collins Gem Dictionairy and Thesaurus as the other ones I had were out of date. There is a section where it talks about spelling, punctuation etc.
And the apostrophe with decades came up. Just wanted to confirm whether this is correct.
“An apostrophe is used in front of two figures referring to a year or decade.
French students rioted in ’68 [short for 1968]
He worked as a schoolteacher during the 60s and early ’90s.
They are suggesting shortening the year and placing the apostrophe before rather than yours where you put it after the year in full.
Any thoughts?
P.S I’m becoming more alert on these things more than ever!
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Don’t you just hate it when you have to use an apostrophe in that way? My heart sinks when I know I’m going to have to refer to individual letters of the alphabet, or phrases such as “no if’s or but’s”. “Do’s and don’ts” is another. (Why not: “Do’s and don’t’s”?) None of it looks right.
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…and I’ve just found this in the Oxford Dictionary of English (I was looking up ‘maybe’ for a different reason):
“No ifs, buts or maybes”
I think I like it without the apostrophes.
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There is no entirely happy solution to the problem; there are only better or preferred solutions.
With numbers (“the 1970s”), the plural stands out from the last number. I am growing fond of using capital letters, even if technically inaccurate: “mind your Ps and Qs”; “add an S to make it plural.” Something I see from time to time, and don’t like because it’s unnecessary, is Exhibit “A.” I don’t see how anyone could confuse the A, tied as it is to Exhibit.
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I quite like the use of capitals with no apostrophe. You’re right — it is a bit of an intractable problem.
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Here’s an interesting punctuation issue that came up on a photo of an outdoor ashtray in Devon, UK: The attached caution sign said “No if’s, no butts.” Someone flagged the apostrophe. I think it’s justified, since “if” is not a noun that you could pluralize and “ifs” just looks odd and hard to read.
The sign is obviously a play on the expression “No if’s, and’s or but’s.” You could write it without the apostrophes, as well, since most of us know the expression and would make sense of it.
But then you’d have to make up a new rule when talking about “Minding your ps and qs,” “Dotting your is and crossing your ts,” and many similar expressions. Saying “ps and qs” is even harder to justify than “ifs,” because the letters P and Q are in fact nouns that could be pluralized–yet “ps and qs” looks horrid to me.
One middle-ground solution is to italicize the letter (P, Q, etc.) only, leaving the plural “s” in regular font. A lot of effort when an apostrophe would work as well, huh?
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