“In the long term”

http://books.google.com/ngrams/graph?content=in+the+long+term%2C+in+the+long+run&case_insensitive=on&year_start=1800&year_end=2008&corpus=15&smoothing=3&share=&direct_url=t4%3B%2Cin%20the%20long%20term%3B%2Cc0%3B%2Cs0%3B%3Bin%20the%20long%20term%3B%2Cc0%3B%3BIn%20the%20long%20term%3B%2Cc0%3B.t4%3B%2Cin%20the%20long%20run%3B%2Cc0%3B%2Cs0%3B%3Bin%20the%20long%20run%3B%2Cc0%3B%3BIn%20the%20long%20run%3B%2Cc0

For what it's worth, there's not a lot of difference at the BBC website, 473 for "in the long term", 517 for "in the long run". And at the Economist it's even closer: 480 to 485 respectively. But these are both British, of course, and if you go to jayles's Ngram link and narrow it down to British books and American books, the use of "in the long term" in books seems somewhat more popular in the UK (1/3) than in the US (1/5).

There is a small problem with the figures for "in the long term", however. In two of the first ten entries at the Economist, for example, the expression is being used adjectivally - "in the long term value", "in the long term trend", although there are none like that in the first ten entries at the BBC, nor inthe first ten collocations at Ngram.

http://books.google.com/ngrams/graph?content=in+the+long+term+*%2Cin+the+long+run+*&case_insensitive=on&year_start=1800&year_end=2008&corpus=18&smoothing=3&share=&direct_url=t2%3B%2Cin%20the%20long%20term%20*%3B%2Cc0%3B%2Cs0%3B%3Bin%20the%20long%20term%20the%3B%2Cc0%3B%3Bin%20the%20long%20term%20to%3B%2Cc0%3B%3Bin%20the%20long%20term%20it%3B%2Cc0%3B%3Bin%20the%20long%20term%20and%3B%2Cc0%3B%3Bin%20the%20long%20term%20is%3B%2Cc0%3B%3Bin%20the%20long%20term%20by%3B%2Cc0%3B%3Bin%20the%20long%20term%20as%3B%2Cc0%3B%3Bin%20the%20long%20term%20than%3B%2Cc0%3B%3Bin%20the%20long%20term%20if%3B%2Cc0%3B%3Bin%20the%20long%20term%20they%3B%2Cc0%3B.t2%3B%2Cin%20the%20long%20run%20*%3B%2Cc0%3B%2Cs0%3B%3Bin%20the%20long%20run%20to%3B%2Cc0%3B%3Bin%20the%20long%20run%20the%3B%2Cc0%3B%3Bin%20the%20long%20run%20it%3B%2Cc0%3B%3Bin%20the%20long%20run%20be%3B%2Cc0%3B%3Bin%20the%20long%20run%20than%3B%2Cc0%3B%3Bin%20the%20long%20run%20by%3B%2Cc0%3B%3Bin%20the%20long%20run%20is%3B%2Cc0%3B%3Bin%20the%20long%20run%20they%3B%2Cc0%3B%3Bin%20the%20long%20run%20a%3B%2Cc0%3B%3Bin%20the%20long%20run%20and%3B%2Cc0

Generally, I reckon if something's good enough to be printed in the Economist, it's good enough for the rest of us. Some examples:

"So technological progress squeezes some incomes in the short term before making everyone richer in the long term"

"That could have profound effects, in the long term, on the economy and the markets"

" ... suggest though that economic conditions are not repeatable in the long term."

It seems that "in the long term" is especially used when contrasting with the short term, and it seems to be often used at the end of the sentence.

Sorry, that link won't work. I forgot PITE doesn't like asterisks in web addresses.

The idiomatic phrases are "in the long run" and "over the long term." "In the long term" isn't wrong, it just sounds odd to the experienced reader. If you care, go with the standard idiom.

It shouldn't really sound odd, as "in the long term" appears to be more common than "over the long term", both in the US and Britain, but especially in Britain. At Ngram (published books)- "in the long term" figures twice as strongly as "over the long term" (although the difference for American books is markedly smaller). The difference is even greater at Google Books: "in the long term" - 15,000, "over the long term" - 6,000. On general search, ther incidence is about the same.

NY Times "in" - 29,400; "over" - 24,000
Washington Post "in" - 22,700; "over" - 13,700
Times (London) "in" - 22,700; "over" - 770
The Economist "in" - 41,000; "over" - 21,000

There is the proviso noted above, that with the "in" version, it sometimes acts as an adjective, but the majority of cases seem to be the stand -alone expression. (None of the ten most common followers at Ngram are adjectives).

In Britain, at least, I would suggest that the "in" version is more idiomatic than the "over" version.