Dear TM:
You wrote:
> Hello, I have been reading your sight and love it. I am still a little unsure of how to correctly use the following:
>
> “Since the early 1970s, the overall stock market, as measured by the S&P 500 has risen every Presidential election year except the year 2000, during which we were in the midst of a recession.”
>
> Is it 1970s or 1970’s – which is correct and why?
>
> Also, the below is even more confusing to me:
>
> “The original 1960s Medicare plan only cost a few million dollars initially, but has grown into a behemoth program, severely challenging the flexibility of spending restraint.”
>
> This was originally, “1960s'” which is correct and why?
>
> In reading the sight, I believe the rules about “Nouns Expressing Measurement” apply, meaning they should both be “1970s & 1960s”, am I correct?
>
> This is for a publication going out this week, so if possible need an answer a.s.a.p. We are all debating over this and you are the final say-so.
>
This is a question that authorities differ on. A hundred years ago, nearly anyone writing this would have written out the date in letters: “nineteen sixties.” The basic rule about using apostrophe s for plural limits you to acronyms (and not all authorities agree on that) and words and numbers naming themselves. Because these dates resemble numbers naming themselves, people have started using an apostrophe s for the plural. I will give you two answers.
1. Either way is accepted today. Whichever you choose, be consistent.
2. Having said that, “1960s” without the apostrophe is historically more correct and technically more accurate. The reason is simply that “1960’s” could be a possessive for the year, e.g. “Do you recall who won 1960’s World Series?” If you use “1960s” for the plural and “1960’s” for the possessive, this helps your readers. I might even suggest that the “1960s Medicare plan” should read “1960s’ Medicare plan,” since it really is plural AND possessive.
P.S. I’ll never forget who won 1960’s World Series. I was there at the seventh game. 🙂