Audit-Firm Profitability: Determinants and Implications for Audit Outcomes
利用英国大型审计事务所与客户公司的财务数据，研究审计事务所盈利能力的驱动因素及其对审计质量的影响，发现四大与非四大事务所的盈利结构不同，且盈利能力越强审计质量越高。
We use a novel dataset that links audit-firm and client-firm financial statement information from the U.K.’s largest audit firms to examine drivers of audit-firm profitability and its implications for audit outcomes. We first explore the determinants of audit-firm profitability and conclude that Big-4 and non-Big-4 audit firms have fundamentally different profitability structures. Big-4 firms have higher profit margins than non-Big-4 firms. Furthermore, Big-4 profitability increases with client size and complexity, while non-Big-4 profitability is higher for smaller, private-firm clients. Next, we examine the relation between audit-firm profitability and audit outcomes. Using a battery of alternative outcome measures, we find that more profitable audit firms deliver higher audit quality. In supplemental analyses we show that the positive relation between audit-firm profitability and audit outcomes is generally stronger for more influential and illiquid clients (i.e. when auditors are exposed to more litigation risk). Our inferences are robust to several endogeneity controls, such as using an instrumental variables approach, controlling for client-firm and audit-firm fixed effects, employing lead-lag and changes specifications, and assessing bias from correlated omitted variables. Our study contributes to the literature by being the first to provide insights into audit-firm profitability and examine in detail its implications for audit quality.