審計客戶重要性與盈餘管理：以五大事務所組別為觀察標的

Abstract

由於國內合夥人的盈餘分配與組別的業務績效息息相關，故瞭解經濟誘因對各組別會計師審計品質的影響尤為重要。本研究以國內五大事務所內部組別為對象，探討審計客戶佔事務所內組別業務比重的大小，是否會影響會計師允許客戶管理當局操縱盈餘的空間。實證結果顯示，當審計客戶的組別重要性愈高時，會計師允許管理當局操縱盈餘的空間愈大;但隨著組別規模愈大而單一客戶的相對重要性遞減時，會計師允許客戶管理當局操縱盈餘的彈性也會降低。此外，本研究亦發現，會計師允許客戶管理當局盈餘操縱的方向是不對稱的。對於裁決性應計數為正的公司，會計師會因客戶的組別重要性大，而允許客戶管理當局有較大的向上操縱空間，然而隨著組別規模愈大，會計師允許客戶管理當局操縱盈餘向上的空間有縮小的趨勢。另一方面，對於裁決性應計數為負的公司，客戶的組別重要性卻不影響會計師允許客戶管理當局操縱盈餘向下的空間。從本研究可知，在台灣目前的審計環境下，即使是五大事務所，會計師在審計決策過程中仍偏重於經濟誘因的考量，而忽略審計失敗後可能發生的聲譽(訴訟)損失。最後，我們發現在規模較小的組別中，上述審計品質不佳的情形較規模較大的組別更為嚴重。

As profit sharing among partners of a CPA firm has important bearings on the operating performance of the associated audit group, it is pivotal to explore whether economic incentives affect the audit quality of audit groups within CPA firms. This study examines whether auditors allow more discretionary accruals (hereafter DAs) to clients from which the revenue account for a higher proportion of total revenues from audit group of the Big Five CPA firms. The evidence indicates that more important clients for the audit group have higher level of DAs. However, if audit groups have relatively higher clientele, auditors tend to permit less DAs because of less economic dependence on a single client. Meanwhile, we also find evidences of association between auditors’ economic incentives and different directional DAs. For companies with positive DAs, auditors are found to allow more income-increasing accruals for more important clients of the audit group. However, for audit groups with large clientele, the effect of client importance on auditors’ decision to allow income-increasing accruals declines. On the contrary, we did not find similar results for companies with negative accruals. In sum, we conclude that, even within Big Five CPA firms, economic incentives of auditors could overwhelm CPA firms’ reputation, and thus cause auditors to report favorably to more important clients of the audit group.