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Five times below, 150% less, etc.
Nowhere to Go But Up
By Evan Jenkins
It wasn't clear in any of these examples what the writer and editor meant, because the math they used doesn't exist.
An expert, we were told, said a proposed power plant "would use 150 times less cooling water per kilowatt that neighboring older plants." Multiplying anything by a positive number like 150 can only increase the amount we're dealing with. Maybe the expert meant the new plant would use one one-hundred-fiftieth as much water. Or maybe not.
Rates of cancer from air pollution, another article said, vary widely, with New York City "four times the national average" (okay so far) and one rural county "five times below the average." If we multiply by five we don't end up "below" anything. "One fifth of the average," maybe? Why make the reader guess?
A report on a survey of news practices said tough interviewing was "down 160% over two years." But nothing can go down more than 100 percent; once it drops that far, it's gone. That one was caught in the editing, and the final phrasing omitted numbers. But reductions, decreases and declines of more than 100 percent, which are impossible, are nonetheless reported with distressing frequency.
The confusion about percentages can extend to increases, too. We need to remember that starting with a rise of 100 percent, the numbers are a little tricky. A 100 percent increase doubles what we started with; 200 per cent triples it; 300 percent quadruples it , and so on to 1,000 percent, which is 11 (not 10) times the original number.
—CJR, Jan./Feb. 2001
Addendum, 4/16/01
Jay Jochnowitz, state editor of the Times Union in Albany, N.Y., was prompted by that discussion to get this off his chest:
"As long as you raise the issue of percents, may I put in my 2 percent about the most heinous and hackneyed offense of all: the tendency of sports figures to say their team gave (or is expected to give) 110 percent. If a journalistic oath is ever devised, it should include a special sportswriter's clause on refusing to quote coaches or gym teachers who use this."
Let it be so.
CJR
