Skipping Over the Numbers Can Lead to Serious Misunderstandings

If you are not a natural number cruncher, you may be like one of my clients who says, "When I see big numbers in an article, my brain just skips over them." Unfortunately, skipping over numbers can lead to serious misunderstandings.

Here are three questions to ask that can help you clarify those big numbers.


1. What's the time period? The reported cost or savings of something is completely irrelevant unless you know the length of time over which it is calculated.

For example, the August 11 Wall Street Journal included this headline: "U.S. Is Overhauling Its Nuclear Arsenal." A secondary headline below read, "A $1 trillion revamp begun under Obama is under way as tensions rise with North Korea."

It would be reasonable to assume this means an up-front cost of $1 trillion, which might strike you as outrageous, especially if you know the total U.S. annual budget is around $4 trillion . Yet reading the article would make clear that the $1 trillion price tag is over 30 years. This breaks down to an expense of $33 billion a year, roughly six percent of the $550 billion annual defense budget. A headline reading, "6% of annual defense budget to be spent modernizing the nuclear arsenal," is less likely to make the hairs on your neck stand up in horror.

It's no different than my saying I plan to spend $100,000 fixing up my house, which has a market value of $200,000. If you assume I'll spend this immediately, it sounds shocking. But over 30 years it comes to $3,330 a year, which is a reasonable amount to spend on annual maintenance.

This tactic of lumping together multiple year’s expenditures is frequently employed when someone wants to make an expense or a savings seem far larger than it really is.

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2. Does the number include interest? If I said the average home in Rapid City, SD, cost $648,679, local residents who know the average home price is around $200,000 might call me a liar. Yet the cost of mortgage interest over 30 years on that $200,000 house brings the total to $648,679. This larger number might seem deceptive, because our society refers to the cost of something based on today's cash price, not in terms of the total initial cost plus interest.

3. Did you read the whole article carefully? If you speed read and miss the minutia, numbers can be misleading. In recent weeks, the Rapid City Journal has published several articles on the controversial issue of remodeling or replacing the city's civic center. A July 9 article cited the cost of a new civic center as $182 million; on the second page the cost of a previous proposal for a civic center that was defeated in a public vote was listed as $180 million. A quick read would make it appear the new proposal would cost $2 million more than the previous proposal.

A closer read would show that the $182 million for the new center included interest over 30 years, while the $180 million number for the former included no interest. With interest, the cost of the previous proposal would have been $340 million to $420 million, numbers which did appear elsewhere in the article. If we compare actual cost without interest, the estimated cost of the new proposal is around $100 million to $130 million, which is $50 million to $80 million less than the $180 million cost of the previous proposal.

You don't have to be a "numbers person" to understand big numbers in media reports. You just need (with the help of a calculator, if necessary) to read carefully.