An Effective Display of Unit Price Information

UNIT pricing is an idea whose time has come. As a means of improving consumers' decisions, the posting of unit price information has already been accepted by many groups. Beginning with Massachusetts in 1970, several states have enacted legislation requiring the posting of unit prices for some products.' Many supermarket chains are currently posting unit prices or have experimented with them.2 Finally, consumer advocates are campaigning for the wider adoption of unit pricing.3 The argument for unit pricing is straightforward. First, the posting of unit prices should eliminate any confusion due to price calculation, especially across packages of different sizes. The removal of calculation problems ought, in turn, to encourage meaningful price comparisons and result in more purchases of the most economical items. In spite of the plausibility of this reasoning, and of the broad acceptance of unit pricing, the results of research that measured the effects of unit pricing have been inconclusive. Some studies report high consumer awareness of unit pricing, while others show a low level of awareness.4 Some studies indicate a change in purchasing patterns, while others report no change.5 One purpose of the researdh reported in this article is to resolve the paradox between the apparent usefulness of unit price information and the failure of unit pricing to change consumer purchasing habits.