The coefficient on SUSPECT_NI is positive (0.0497) and significant at the 5% level (t ¼ 4.99). The coefficient indicates that the mean abnormal production costs of suspect firm-years are larger by 4.97% of assets than the mean across the rest of the sample. This is an economically significant amount, given that median production costs as a percentage of total assets for the entire sample is around 79%(Table 1).