Market Discipline in Property/Casualty Insurance: Evidence from Premium Growth Surrounding Changes in Financial Strength Ratings

Analysis of abnormal premium growth surrounding changes in financial strength ratings for a large panel of property/casualty insurers generally indicates significant premium declines in the year of and the year following rating downgrades. Consistent with greater risk sensitivity of demand, premium declines were concentrated among commercial insurance, which has narrower guaranty fund protection than personal insurance. Premium declines were greater for firms with low pre-downgrade ratings, and especially pronounced for firms falling below an Arating. There is no evidence of moral hazard in the form of rapid commercial or personal lines premium growth following downgrades of A-or low-rated insurers.