Asymmetric Impact of Corporate Tax on Stock Market Development: Evidence from The Nonlinear Autoregressive Distributed Lag (ARDL) Approach

The stock market and tax policy are widely considered as two core factors for economic growth in any country. A well-developed and functioning stock market provides information on profit-making of successful investment projects, risk diversification, and efficient resource allocation. In addition to domestic resources, the stock market is also considered a crucial part of the global economy. In recent years most OECD countries, including the United States, have substantially reduced their corporate tax rates to stimulate investments, attract foreign capital, and achieve higher economic growth. Corporate tax cuts in a country are expected to positively affect stock market development by encouraging domestic investments and allowing for profit repatriation by multinational companies and foreign firms which will effectively lead to higher stock market development. Despite an extensive literature examining effects of tax policy and the stock market on economic growth, only a few studies have investigated the relationship between corporate tax rate and stock market development, and these studies have shown mixed results. This study investigates the link between corporate tax and stock market development for a group of nine selected OECD countries for the period of 1980-2018 using both long-run and short-run models. In addition to the Pesaran, Shin and Smith (2001) bounds testing approach to cointegration and error correction modeling using the linear ARDL model, we employ the Shin, Yu and Greenwood-Nimmo (2014) nonlinear cointegration approach to investigate the asymmetric impact of corporate tax changes on stock market development. Our findings indicate that, in the linear model in most of countries in this sample, corporate taxing adversely affects stock market development both in the short run and in the long run. In addition, as the first study using the N-ARDL estimation method to investigate this relationship, the robust and strong statistical results show that the effect of corporate tax on stock market development as a major part of financial market development is asymmetric. We show that corporate tax policies in the short run have a nonlinear, asymmetric impact on stock market development. The magnitude of the impact depends on whether the tax policy is a decrease or an increase in corporate tax. Furthermore, this effect changes among the countries in our study. For instance, the stock market’s reaction to an increase of corporate taxing in the United States is much more rapid than that of decreases of corporate taxing. Corporate tax increases immediately and strongly affect the stock market, but the stock market takes years to incorporate the effect of tax decreases.