Size-Threshold effect in the capital structure-firm performance nexus in the MENA region : a dynamic panel threshold regression model

This paper investigates the nonlinear relationship between capital structure and firm performance in the MENA region using a sample of 499 listed firms over the 2007-2020 period, or 6986 firm-year observations. Specifically, we examine the size-threshold effect in the capital structure- firm performance nexus. To do so, this study applies a dynamic panel threshold regression model (DPTR). The findings show that there is a nonlinear relationship between debt and firm performance (Tobin's Q, ROA, and ROE). Specifically, the threshold values of firm size for the three models are estimated at 9.126 (about $1 million), 15.48 (about $5 million), and 16.816 (about $20 million), respectively, between the low- and the high-sized regimes. In the lower regime, the firm's value (Q) increases when debt increases; however, in the higher regime, this value decreases when debt increases. Furthermore, in the lower regime, the performances (ROA and ROE) of small firms decrease when debt increases; however, in the upper regime, when debt increases, the performances of large firms increase. The results are several robustness tests. These results support the predictions of signal, pecking order, and trade-off theories. Managers of large (small) MENA firms should increase (decrease) the use of debt to improve performance.