Abstract: Growth among 501(c)(3) charitable organizations is generally taken for granted. However, there is almost no scholarship that systematically examines the trend of growth in this critical portion of the nonprofit sector. My research examines the change over a twenty year period in number of economically significant charities, their total revenue, and donations they received while adjusting for inflation and growth in both the economy and within the population of charitable organizations. Data from Forms 990 is compared alongside the consolidated data of America's largest fundraising charities in the Philanthropy 400, an annual ranking published by The Chronicle of Philanthropy. Inflation adjustment of the filing threshold is imperative because the cheapening effect inflation nearly guarantees growth if all filers are indiscriminately included. Categorization of organizations based on the National Taxonomy of Exempt Entities reveals different patterns within the population of charitable organizations. Growth slowed for the population of charities over the last twenty years in terms of number of organizations and total revenue, while concentration is revealed by the largest fundraising charities received an increasing share of overall donations and revenue. Sensitivity analysis reveals the growth trend has nothing to do with the recent recession. A much longer trend suggests the population of charities is reaching a point of industry maturation in an extremely similar trajectory to that previously observed in the market structure of other industries like brewing and automobile manufacturing. This study provides a context for better understanding short term changes among charities and changes among subpopulations of charitable organizations. This study raises significant implications about how the nonprofit sector is measured, the competitiveness of fundraising, and the potential growth of various categories of charities in the coming years
