Tanzania has continued to experience an unprecedented increase in Foreign Direct Investment (FDI) inflows for the past three decades. Using a vector error correction model (VECM) on data on Tanzania for the 1980–2020 period, we find the bi-causality between economic growth and FDI net inflows in the short and long run. The results imply that in Tanzania, FDI is associated with an increase in income; at the same time, economic growth leads to FDI eventually and stirs movements in FDI. In addition, our results show a strong (positive) relationship between the variables, which means that foreign direct investments (FDI) significantly impact the country's financial inflows. We believe that a well-developed and productive local capacity will eventually benefit from FDI. Nonetheless, this is only possible through the provision of incentives to foreign firms so that they may provide positive spill overs to other sectors.

This study contributes to the literature on financial efficiency and growth. We show evidence from the effects of controlling institutional variables given the increase in domestic credit. The domestic credit is adverse, with an insignificant effect on per capita income growth. We make two observations from our findings. First, the negative but insignificant coefficients of the measure of bank credit across all model specifications seem to go against the supply-leading hypothesis, as financial development hurts economic growth; nevertheless, given that the impact is insignificant, this draws more into a neutrality hypothesis of no effect. Second, the findings are likely indications of the underdeveloped state of sub-Saharan Africa's financial system, implying that the present state of the financial systems is not robust enough to be a contributory drive towards enhancing economic growth in the region. However, all models have positive control variables (Inflation and gross fixed capital formation). All coefficients of interactions between credit and institutional quality are statistically insignificant (negative in four of six models).

In this paper, we use the ARDL method to find the Impact of institutional quality on economic growth in Tanzania from 1990 to 2021. The ARDL technique frees variables from residual correlation as all variables are assumed to be endogenous. They distinguish between dependent and explanatory variables in any long-run relationship, identify the co-integrating vectors with multiple co-integrating vectors, and derive the Error Correction Model (ECM) or Error Correction Model (ECM) Vector Error Correction Model (VECM) by integrating short-run adjustments with long-run equilibrium without losing extended-run information. Our results show all adjustment terms in the respective models that have a long-run relationship have correct (negative) signs and are more than one, implying there is convergence in the long run; that is, the models returned to their long-run equilibrium; the rate (or speed) at which this happened ranged between 15% to 106.6% annually. Institutional quality has a significant affirmative (0.047) causal long-run effect on economic growth