세부 계정과목별 고유위험과 감사보수, 감사시간 및 시간당 감사보수와의 관련성 연구

The Relationship between the Inherent Risk of Detailed Accounts and External Audit Hours, Audit Fees and the Hourly Fee Rate - An Analysis before and after K-IFRS Adoption and Whether the Auditor is Big4 or not -

본 연구는 감사인이 세부 계정과목별 고유위험을 감사보수, 감사투입시간 및 시간당 감사보수 등 감사관련 제반변수에 반영하는지 여부를 조사한다. 구체적으로 재고자산과 매출채권 비중 이외의 세부 계정과목(파생상품, 이연법인세, 종속(관계)기업투자 및 퇴직급여부채)별 고유위험을 감사인이 감사관련 변수에 반영하는지가 주된 연구대상이다. 또한, 감사인의 세부 계정과목에 대한 위험 대응이 한국채택 국제회계기준(이하 ‘K-IFRS’)의 도입 이후 및 감사인 유형별(BIG4 및 Non-BIG4 회계법인)로 상이하게 나타나는지에 대한 결과를 제시한다. 추가로, 이러한 세부 계정과목의 고유위험에 대한 감사인의 시기별, 규모별 대응 차이가 감사품질의 변화와 관련되는지를 조사한다. 실증 결과를 요약하면 다음과 같다. 첫째, 감사인은 파생상품 계정의 고유위험을 감사보수에, 종속(관계)기업투자 및 퇴직급여부채 계정의 고유위험을 감사보수 및 감사노력에 모두 반영하는 것으로 나타났다. 둘째, BIG4 감사인 표본에서는 K-IFRS 도입 이후 파생상품 및 종속(관계)기업투자 계정의 고유위험이 높을수록 감사투입시간의 증가가 나타났고, 특히 종속(관계)기업투자 계정의 고유위험은 시간당 감사보수의 하락과도 관련되었다. 이는 K-IFRS 환경에서 연결재무제표의 주 재무제표화 및 그룹감사인의 책임 확대에 따른 연결 감사 프로세스에 대한 BIG4 감사인의 과도한 노력 투하가 원인으로 판단된다. 한편, Non-BIG4 감사인 표본에서는 K-IFRS에 따른 이연법인세 계정의 고유위험으로 인한 시간당 감사보수의 하락을 제외하고는, 세부 계정과목별 고유위험이 감사시간 및 시간당 보수에 미치는 영향은 나타나지 않았다. 셋째, K-IFRS 도입 이후 세부 계정과목별 고유위험과 관련된 감사품질의 하락은 BIG4 및 Non-BIG4 감사인 모두에서 나타나지 않았다. 이는 감사인이 K-IFRS 도입 이후에도 계정과목별 고유위험이나 복잡성을 파악하고, 각 감사인 유형별로 차별화된 감사절차 실행 전략을 통하여 일정수준의 감사품질을 지속적으로 유지하고 있는 것으로 해석된다.

This study empirically analyzes whether auditors perceive the inherent risk of detailed accounts as audit risk and whether the perceived audit risk in detailed accounts is reflected in audit fees, hours and the hourly fee rate. Specifically, other than the proportion of account receivable and inventory which has been known as measurement for inherent risk or complexity of accounts through prior research, we examine whether auditors reflect the inherent risk of detailed accounts such as derivatives, deferred tax, investments on subsidiaries(affiliated companies) and retirement benefits liabilities in audit-related variables. We also investigate whether the auditors’ responses to audit risk after K-IFRS(International Financial Reporting Standards, thereafter ‘IFRS’) adoption are different by auditor type such as Big4 and Non-Big4 auditors, and the differential responses to audit risk by auditor type, in any, are related to the difference in audit quality. Using 10,244 firm-year samples between 2007 and 2014, we find the following empirical results: First, the inherent risks of the derivatives accounts are reflected in the audit fees, and the inherent risks of the investments on subsidiaries(affiliated companies) and retirement benefit liabilities accounts are reflected in both audit fees and audit efforts. And this result in significant decrease in the hourly fee rate and appeared only in Big4 auditors sample. Second, there exist increase in audit hours as a response to audit risk for derivatives, investments on subsidiaries(affiliated companies) accounts, and decrease in the hourly fee rate for investments on subsidiaries(affiliated companies) accounts in Big4 auditor sample. This is presumably due to over investment in audit effort of Big4 auditors to consolidated financial statement audits under IFRS environment which consider consolidated financial statements as primary financial statements and require auditor responsibility for the financial statements of subsidiary companies. In Non-Big4 auditor sample, there is no relationship between the inherent risk of detailed accounts and audit hours after IFRS adoption except for decrease in hourly audit fee. This means Non-Big4 auditors strategically respond to increased audit risk by using more experienced auditors. Third, there is no audit quality decline in any sample of Big4 and Non-Big4 auditors, implying that auditors keep audit quality at a certain level, even though they have perceived audit risk and complexity of the detailed accounts and performed different audit procedures by auditor type. We contribute to the existing literature by extending prior research as follows. First, this study comprehensively shows the association between the inherent audit risk and audit-related variables like audit fees could be decomposed into the inherent risks of detailed account to derivatives, deferred tax, investments on subsidiaries(affiliated companies) and retirement benefits liabilities accounts. Second, this study provides an explanation about the different profitability decline of Big4 and Non-Big4 rasied by prior research, as a differential risk response process by auditor type. Third, this study suggests auditors have differently responded to the inherent risk of detailed accounts but have kept audit quality to the certain level, when there is a increase in auditors’ liability. Finally, this study provides current literature with new audit risk measurement method about detailed account such as derivatives, deferred tax, investments on subsidiaries(affiliated companies) and retirement benefits liabilities accounts.