Per cent, percent or %?

What to write: per cent, percent, or %? Respected style guides disagree.

Dear Rachel
As I write Tech Universe I frequently come across paras like this:

My question is: why on earth do so many publications write 'per cent' as words rather than using the much loved (by me) % symbol. It seems to me 37% is instantly clear, easy to read, plain and simple, while 'per cent' and 'percent' aren't.

 Can you shed any light on this? Any plain language thoughts?

Cheers,
  Miraz Jordan

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Hi Miraz
This question has often puzzled me too. Guess people learn that early in life as a "rule" (sarcastic quote marks, of which I strongly disapprove) early in life.

The writer was following this dubious principle: use the (US) word instead of the symbol in prose, even if you give the number in numerals.

I've had a quick flick through some of my style guides and found ambiguity, contradictions and wriggle room.

• Per cent (US percent) is required in running text. (New Oxford Dictionary for Writers and Editors) 
• Use the sign % instead of per cent. (The Economist)
• Use numerals with percentages. Use either the word percent or the percent sign (%) in text — as long as you're consistent. Consider that the percent sign saves space, and if a passage contains two or more percentages, the percent sign is easier to spot, making it easier to compare the numbers. (Yahoo! Style Guide)

Cheers
Rachel

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:-) Mud, glorious mud!

Thanks for all that. What a splendid mess!

%%%%%% !

Cheers,
Miraz Jordan
Knowit.co.nz

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