*4.8. Control Variables*

In this study, we controlled the firm size by taking the natural logarithm of total assets (Nguyen et al. 2014; Richardson et al. 2003). The second control variable was leverage, which was measured as the ratio of total debt to total assets (Arthurs et al. 2008). Growth opportunities also affect the firm value, so their effect was also controlled. This was calculated as the difference between current year sales and previous sales divided by the previous sales (Gill and Biger 2013). We also controlled the firm age, which was calculated as the number of years for which the firms had been listed in the stock exchange (Shan 2015). The summary of all the variables is given below in Table 2.


#### **Table 2.** Summary of the variables.
