The Unbundling of Advertising Agency Services: An Economic Analysis

Abstract We address a puzzle surrounding the shift from bundling to unbundling of U.S. advertising agency services and the slow pace of change over several decades. We model an agency’s decision as a tradeoff between the fixed cost to the advertiser of establishing a relationship with an agency and pecuniary economies of scale from media services provision. Using micro-data from the U.S. Census of Services for 1982-2007, we find agencies are more likely to unbundle with increasing size, diversification and higher media prices, and less likely with increasing age, larger media volume, and an interaction between media prices and volume.