How CDP calculates its public media fundraising indexes

Contributor Development Partnership’s National Reference File collects membership, donor and revenue numbers from more than 170 public media stations. Gifts are categorized by their respective fundraising sources, including direct mail, email, canvassing, online, Passport, telemarketing, texting, events and major giving. The dataset, which CDP uses to calculate its fundraising indexes, includes only fulfilled payments and gifts from individuals.

Each participating station is categorized according to the size of its donor file. Small stations have fewer than 15,000 active donors; medium stations have 15,000 to 40,000 donors; and large stations have more than 40,000 donors. Categories of stations’ licenses — TV, radio or joint — provide additional insights into trends.

CDP weights the percentage change reported by each station according to the size of its membership file. Stations that raise the most revenue are weighted higher than those that raise less.

The weighted median derived from calculations for each index represents fundraising performance across all stations.

Index methodology

Each of the five indexes tracks key fundraising metrics over the previous three months and compares the results to the same period in the prior year.

After calculating the year-over-year percentage change for each station during the reporting period, CDP uses that data to determine the weighted median percentage change, which represents performance on that metric by all stations.

The Passport User Index, which is derived from Passport viewing data collected by PBS, represents changes in streaming usage among unique viewers per station.

Membership Revenue Index — change in total membership revenue

New Donors Index — change in new donors added to stations’ membership files

High-dollar Gifts Index — change in membership gifts of $500 and higher fulfilled during the reporting period

Sustainers Index — change in the number of donors who made a sustaining payment

Passport User Index — change in the number of unique Passport users per station who watched any amount of content, based on viewing data collected from PBS on behalf of nearly 100 public TV stations

CDP is an independent public benefit corporation with a mission to support public media fundraising. It created and built the National Reference File as an analytic tool to help stations grow their active donor files and increase net revenue.