재무이익-세무이익의 일치성, 보고이익 차이의 일관성과 이익의 정보효과

Abstract

본 연구는 외환위기 전과 후로 구분하여 재무이익과 세무이익의 정보효과 뿐만 아니라 이익조정과 세무계획이 재무이익과 세무이익의 정보효과에 미치는 영향을 개별효과와 교차효과로 구분하여 분석하였다. 아울러 보고이익의 일치성과 보고이익 차이의 일관성이 재무이익과 세무이익의 정보효과에 미치는 영향을 분석하였다. 분석결과는 다음과 같다. 첫째, 재무이익의 정보효과는 일관되게 양(+)으로 나타났으나 세무이익의 정보효과는 외환위기 전에는 음(-)인 반면 외환위기 후에는 양(+)으로 반전하였다. 이는 외환위기라는 경제적 사건 이후 자본시장 참여자들이 경영자의 재량권이 적은 세법에 의해 산출된 세무이익을 기업의 성과를 평가하는데 이용하고 있음을 시사한다. 둘째, 이익조정 수준이 높을수록 재무이익의 정보효과는 감소하고 세무계획 수준이 높을수록 세무이익의 정보효과는 감소하는 것으로 나타나 개별효과가 존재하였다. 그러나 이익조정이 세무이익의 정보효과에 미치는 교차효과는 존재하지 않고 세무계획이 재무이익의 정보효과에 미치는 교차효과는 기간별로 다르게 나타났다. 셋째, 보고이익의 일치성과 보고이익 차이의 일관성이 증가할수록 재무이익의 정보효과는 증가하는 반면 세무이익의 정보효과는 감소하는 것으로 나타났다. 이는 보고이익의 일치성과 보고이익 차이의 일관성이 증가할수록 성과측정치로서 재무이익의 정보효과는 증가하는 반면 재무이익과 다른 수치로 세무이익이 보고되는 유연성은 낮아지므로 세무이익의 정보효과는 감소하는 것을 시사한다. 본 연구의 의의는 다음과 같다. 첫째, 재무이익의 정보효과가 세무이익의 정보효과보다 크다는 일관된 결과를 제시하였다. 둘째, 이익조정이 재무이익의 정보효과에, 세무계획이 세무이익의 정보효과에 미치는 개별적인 효과뿐만 아니라 이익조정이 세무이익의 정보효과에, 세무계획이 재무이익의 정보효과에 미치는 교차효과도 모형에 포함하여 분석함으로써 종합적으로 보고이익의 정보효과를 분석하였다. 셋째, 이익조정과 세무계획이 결합하여 미치는 영향을 분석하기 위해 보고이익의 일치성 및 보고이익 차이의 일관성을 포함하여 재무이익과 세무이익의 정보효과에 미치는 영향을 분석하였다. 보고이익의 일치성과 보고이익 차이의 일관성이 이익조정과 세무계획을 통제한 후에도 증분효과를 가진다는 연구결과는 보고이익의 일치성과 보고이익 차이의 일관성에 영향을 주는 회계제도나 회계방법 및 세무계획의 적용이 보고이익의 정보효과에 추가적인 영향을 미친다는 시사점을 제공한다. The main purpose of this paper is to examine whether the information content of book income and taxable income depends on the book-tax conformity, and the book-tax difference consistency, and whether such an effect is incremental to the separate effects of earnings management and tax planning on the informativeness of book income and taxable income. The book-tax conformity and the book-tax difference consistency over time depend on whether the firm decides to engage in earnings management and tax planning. Book-tax conformity refers to the flexibility that a firm has to report taxable income that is different from pretax book income, and consistency of book-tax differences refers to the consistency over time of the relation between book and taxable income. Conformity arises from the similarity between accounting standard and tax laws, and consistency arises from the selection of consistent book and tax accounting methods, even when different methods could have been used for each. We measure book-tax conformity based on the root mean squared error obtained from industry-specific estimates of regression equation which estimates the extent to which pretax book income explain current tax expense, and measure book-tax difference consistency based on the standard deviation of the discretionary component of the differences between book income and taxable income. We measure information content based on correlation with contemporaneous stock returns. Earnings management refers to the use of discretionary accruals to manipulate reported income; we measure earnings management based on the standard deviation of estimated discretionary accruals. Tax planning refers to efforts to reduce tax payable by reducing taxable income; we measure tax planning based on the current effective tax rate, the ratio of current tax expense to pretax book income. In our analysis, we use Korean listed firms with available Korea Investors Services(KIS)-Vaule data from 1985 to 2012. We restrict the sample to non-financial, non-utility firms and have a december year-end. Additionally, firm-years with missing financial data and firm-years which can not estimate effective tax rates are excluded. We delete observations in which any continuous variable lies beyond the highest and lowest 1% of the distribution for that variable to control for outliers. These data requirements result in a sample of 6,989 firm-year observations which consist of 2,485 observations before the financial crisis(1991-1997) and 4,504 observations after the financial crisis(2000-2012). We conduct tests documenting (1) the incremental effect of earnings management and tax planning on the relative information content of book income and taxable income, and (2) the relation between book-tax conformity and relative information content of book income and taxable income, and (3) the relation between book-tax difference consistency and relative information content of book income and taxable income. We find that both earnings management and tax planning have opposing effects on the information content of book income and taxable income. However, we do not find a significant relationship between earnings management and information content of taxable income after controlling for tax planning. In order to better capture the joint effect of earnings management and tax planning on the informativeness of book income and taxable income, we introduce book-tax conformity and book-tax difference consistency measure. Consistent with our expectations, we find that the information content of book income is significantly greater for firms with high book-tax conformity and firms with more consistent book-tax differences. But contrary to expectations, we find that the information content of taxable income is significantly lower for firms with high book-tax conformity and firms with more consistent book-tax differences. Based on our results, we conclude that the book-tax conformity and the consistency of book-tax difference captures the effects of both tax planning and earnings management on the information content of book income and taxable income. The effect of taxes on financial reporting has been the focus of extensive research. Our study contributes new findings in this research area. To summarize, we find that while earnings management affects the information content of book income, and tax planning affects the information content of taxable income, tax planning also affects the information content of book income. This finding provides a better understanding of the conditions under which tax rules affect the informativeness of book income. Importantly, we find that book-tax conformity, and book-tax differences consistency affects the information content of book and taxable income, and this relationship is incremental to the separate effects of earnings management and tax planning. These findings suggest that book-tax conformity, and book-tax difference consistency captures the effects of both earnings management and tax planning on the information content of book income and taxable income.