Some folks decided to study the calling habits of 5.3 million people over an 18-month period. 350 million phone calls later, they came to an almost obvious conclusion: Prepaid cellphone users make and return fewer calls than their postpaid counterparts. You can click on the image to take a closer look at the graphs. Initially the study done at the Aalto University School of Science and Technology, Finland, was intended to analyze reciprocity—the likelihood of an individual receiving as many calls in return as he or she makes. But during the course of the research, a clear difference was discovered in the calling habits of prepaid and postpaid users: Postpaid users tend to be more prolific, having on average 5.41 people they call.

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Prepaid Cellphone Users Less Likely to Return Calls [Data]