How Non-Rounded Numbers Affect Consumer Decisions

• How do customers evaluate price numbers?
• Does the brain see 80% and 81.36% differently?

A research study in 1988 looked at how people react to comparisons between two numbers, specifically 80% and 20% in fat content of hamburger. What was found was that how the question was framed made a huge difference. Consumers were more likely to buy hamburger if it was labeled as “80% fat-free” than if the label read “Contains 20% fat.” The brain sees “80% Fat-Free” differently from “20% Fat.” The perceived difference is the framing effect.

That study used round numbers ending in 0. What if more precise, non-round numbers had been used instead? A series of studies has shown that non-round numbers affect people’s perceptions of price. People tend to see non-rounded-off numbers as more precise and authoritative. Such numbers tend to shift the brain’s attention to calculate more carefully or to simply round the numbers off crudely to make comparisons.

Neuromarketing Research into Non-Rounded Numbers

A group of researchers conducted several studies to clarify the effect of using non-rounded numbers in attribute comparisons. What they discovered generated some surprising conclusions. Some volunteers were asked to evaluate the quality of ground beef labeled as “80% Fat Free” or “81.64% Fat Free.” Surprisingly, “80% Fat Free” ground beef was rated higher in quality.

Other volunteers were asked to evaluate the quality of ground beef labeled as “20% Fat” or “18.36% Fat.” The “18.36% Fat” beef was rated lower in quality.

Non-Rounded Numbers Shift the Brain’s Comparisons

Here is how the researchers explained the observation. When the beef was labeled “80% Fat Free,” little attention is paid to the number because “80%” is simple for the brain to process.

This more complex number requires a reference point of “100%” to process. Compared to “100% Fat Free,” “81.64% Fat Free” beef appears to be lower in quality.

To verify the findings from that initial study, the researchers conducted additional studies. They tested volunteers to measure their attention on the numbers, using eye-tracking equipment. They also looked at whether presenting numbers in boldface fonts made a difference. In all, six studies were carried out. The results of all studies indicated that the use of non-rounded numbers caused a negative shift in evaluations, both for larger and smaller numbers being compared.

The framing effect bias still operated, but what was being compared changed. In the case of rounded numbers, the two numbers are compared against each other. When non-rounded numbers are used, the comparison is against an ideal number like 100% and 0% instead. The non-rounded numbers appear to shift the brain’s calculations. It switches from rough, emotion-based comparisons to more calculated comparisons against simple, standard numbers.

Consider How You Present Numbers for Comparison

In a marketing environment, the conclusions from this Neuromarketing study complicate price and value framing decisions. If your goal is to have consumers quickly compare two price or value numbers for a decision, in either positive or negative framing, use round numbers to keep focus on the actual comparison. However, if you want consumers to compare high or low numbers against an ideal standard, use non-rounded numbers to shift the brain into a more rational consideration. Here is an example of positive framing.

Here is an example of negative framing.

The framing effect bias is just one of the ways you can present your marketing and advertising to influence consumer decisions. A thorough understanding of how the brain makes decisions is essential to successful marketing and sales presentations.