Spread between the Moody’s Aaa-Rated Corporate Bond Yield and the Yield on Municipals: Co-integration Analysis

Abstract

While the research linking interest rates to government deficits is extensive, the impact of other tax-related variables is uncommon. This study seeks to add to the literature on credit markets by exploring the impact of not only the budget deficit but also average effective personal income tax rates and personal income tax evasion as explanatory variables. To the best of our knowledge this study is the first study to recognize the joint importance of all of these fiscal variables. We utilize data covering the post-Bretton Woods period from 1971 through 2016 to analyze the impact of the three variables in order to shed light on the spread between the real interest rate yields on Moody’s Aaa-rated corporate bonds and high quality municipal bonds. Estimations reveal that the higher the average effective federal personal income tax rate, the greater the differential between the yields on corporate bonds and tax-free Municipals. Furthermore, it is found that the higher the adjusted gross income gap, the greater the real yield spread between Moody’s Aaa-rated corporate bonds and high quality municipal bonds. Finally, the greater the primary budget deficit, the greater the spread as well.