Editor's note: Thayer Allison is research manager with Compassion International, Colorado Springs, Colo.

Many enterprises depend on long-term relationships with clients. Banks, insurance companies and many non-profit organizations provide a service or benefit that is realized over a long period of time. In return their clients or donors send in regular payments - usually called premiums - to the organization.

For such organizations there are two parts to the growth equation: acquisition of new clients and retention of existing clients. Much attention is given to the acquisition of new clients, but retention studies are few.1 This article presents a method of measuring and analyzing retention of sponsors in a child sponsorship organization.

Compassion International is a Christian non-profit organization that provides a wide range of benefits for about 18O,OOO children in 22 countries around the world. Compassion has been linking sponsors from the U.S. with needy children around the world since 1952.

Potential sponsors are made aware of Compassion's ministry through word of mouth, magazine ads, radio, TV, and other means. When a person agrees to become a sponsor they are linked to a specific needy child. The sponsor receives letters from the child as well as periodic updates from the project about the child's progress. The sponsor sends $24 each month to Compassion to provide for these benefits for the child.

The question of interest for this article is: How long does the average sponsorship last? It seems like a simple question but once one delves a little deeper it is not so simple.

The most popular statistic used to describe the "typical" case when the distribution is highly skewed is the median, the middle value. The distribution of Compassion's sponsorship tenures is extremely skewed. (See Figure 1). There are many sponsors who are in the early months of their tenure. ...