The effect of the WPPSS crisis on the tax-exempt bond market

The 1983 default of the Washington Public Power Supply System (WPPSS) was the largest municipal default. Some writers contend that the default affected the entire municipal bond market. This study examines the effect of key WPPSS‐related events on the general municipal market, tax‐exempt public power district bonds, and WPPSS bonds, respectively. The results show that although certain events significantly affected all WPPSS bonds, these events did not affect the general municipal bond market or non‐WPPSS public power bonds. The use of a standard event‐time methodology with daily bond prices (as opposed to monthly yields) appears to provide a more powerful test of the effect of a municipal crisis on the tax‐exempt bond market.