Less than or fewer than

[ChessieFL]

I am having an argument with communications person at work.

He says it should be 'fewer than 2 years' membership'

I think it should be 'less than 2 years' membership'

Who is right?

[Felyne]

I don't actually know for sure but I'd lean toward 'less', like you. 'Fewer' would be more appropriate if it was a precisely measured number of years, whereas time sort of continues on so to me 'less' would be more correct.

[Scootergrrrl]

Less than normally refers to an amount, and fewer than to a number, but even though your sentence has a number in it, you're taking about a whole period of time rather than two individual years, so it would be less than, IMO. (Newspaper sub-editor and occasional copy writer here!)
Try not to crow too much

[tribpot]

It's less than - fewer than two years' membership sounds very odd.

This explains it quite well - time, distance, money and weight are exceptions to the rule about 'things you can count' taking fewer (e.g. 'five items or fewer' in the supermarket). This may be because we think of time as a single block so treat it as a singular.

In your specific example you're also doing an implicit comparison, so is your membership less than two years?

[BoGrainger]

I thought we all agreed it was 'fewer than 10 items' that was correct at the supermarket checkouts. Is this any different? Although I would prefer to say less myself!

[BoGrainger]

I see tribpot. I'd hate to be learning English as a foreign language!

[tribpot]

Well indeed, BoGrainger, although every language has its mad quirks, and nearly all native speakers struggle on a few things in their own language that other speakers of it have learnt by rote. I had to have a very long conversation with some Mexican friends about how to spell sesión académica because they couldn't work out whether sesión had a z, a c or an s in the middle of it (all three can have the same sound in Latin American Spanish) and then they couldn't figure out where the accent went. To me it was obvious because I had learnt these rules rather than grown up there.

[geekaMaxima]

Fewer is for counting whole units when you don't want to consider dividing them into smaller fractions - 10 items or fewer, fewer than 3 children, fewer than 730 days' membership...

Less is for quantifying amounts that can be fractionated - £20 or less, less than a kilo, less than 2 years' membership.

[ChessieFL]

Thanks all!

[MrsHathaway]

Less.

A person might have been a member for (eg) fifteen months. Fifteen months is less than two years, and it would be meaningless to say it was fewer than two years.

[MrsHathaway]

By the way, it is more subtle than "stuff you count" and "stuff you measure".

My favourite example of this is the fact that the average* number of legs on a human being is less than two.

*mean