Graphical information has been widely used in businesses and organizations to display, report and analyze financial information. If the graphical information is inadequately manipulated and employed like the distorted graphs, it may well mislead peoples’ judgment and hence lead their company/organization into a disaster. The study of Mather et al. (Accounting and Business Research 35(2), 147-159, 2005) shows that the graphical distortion of bar chart can be measured by using the relative graph discrepancy index (RGD). The purpose of this research is to find out what level of measurement distortion will mislead users by conducting an experimental study. Research results show that financial graphs tend to mislead users when they are distorted by over ±5 % of the RGD. This threshold should be employed as a means for auditing the related graph distortions.