The Reinsurance Network Among U.S. Property-Casualty Insurers: Microstructure, Insolvency Risk, and Contagion

Reinsurance is the primary source of interconnectedness in the insurance industry. As such, reinsurance connectivity provides a transmission mechanism for financial shocks and potentially exposes insurers to contagion and systemic risk. In this paper, connectivity within the U.S. property-casualty (P/C) reinsurance market is modeled as a network. We model the network of all primary insurers and reinsurers in the market. We analyze all bilateral reinsurance counterparty relationships (domestic and foreign) of U.S. P/C insurers, and we model both intra- and inter-group transactions. We extend the prior literature by providing a detailed examination of the reinsurance network structure, including network density, network components, centrality of individual insurers, and sub-network analysis for top insurers and for insurance groups. Our analysis of contagion and insolvency risk reveals that even the failure of the top 10 in-degree or in-strength insurers with 100 percent loss given default would not lead to widespread insolvencies in the U.S. P/C insurance industry.