Eight times less or one eighth as much?

A loyal reader writes:

As an avid reader of your column in the FT, I thank you for your continued focus on bringing a rational and humourous viewpoint and solution to everyday issues.
However, the column this weekend had the statement that something was “eight times less” than something else (CO2 emissions, I believe).
As any math teacher (and English) could tell you, something which is a whole number (eight for example) multiplied by some other figure will always result in a  larger outcome.
Perhaps you meant to say 1/8th (one-eighth) as much? This is the correct, and preferred way to express a reductive comparison…

I knew there would be complaints when I wrote it. Some people have expressed similar criticisms far less politely than this.

My response:

I regard “eight times less” (or for discrete quantities eight times fewer) as inverting the operation “eight times more”. I am not convinced by the complaints, largely because I think eight times less is unambiguous. Clearly it means “divide by 8″ not “multiply by minus 8″ – you hint that this is perhaps what eight times less must mean, but does anybody believe this?
Your own “preferred” approach is also unambigious but cumbersome.

But I would be interested in what other people believe about this and whether there are any arguments against what I wrote.

Tim Harford’s blog

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Tim, also known as the Undercover Economist, writes about the economics of everyday life.