Bank networks in Türkiye

Abstract

This thesis analyzes the loan network and cross-border network of banks in Türkiye. The impacts of two developments during the studied period between 2007-2019 that significantly affected the credit market, the increase in Treasury-backed guarantees and the exchange rate shock, on these bank networks were also investigated. In the first study, we introduce a novel measure of bank interconnectedness. Using more than 44 million loan observations during the period of 2007–2016, we construct a projected loan network that emerges from the banks’ lending to common firms. Then, we investigate the relation between banks’ loan portfolio riskiness and their connectedness. Our findings suggest that highly connected banks seem to manage their overall portfolio risk better. In the ends of the first quarter of 2017, the Treasury support for the sureties given by the Credit Guarantee Fund of Türkiye (CGF) increased to 12.5-fold and affected credit market significantly. In the third chapter, We investigate whether investor reactions to the announcement of the increase in Treasury support in CGF guarantees are in line with the stated aim of the program. We find that investors perceived the increase in Treasury support to benefit both firms and financial institutions. In the fourth chapter, extending our sample period in the first study, we investigate how CGF schemes changed the bank-loan network in Türkiye. We also find that CGF schemes support the negative relation between the bank connectedness and loan portfolio riskiness. On the other hand, banks’ loan portfolio riskiness increases with the schemes. Finally, considering the impact of currency shock in 2018 on the banking system, in the last chapter we study the cross-border bank network in Türkiye. We find that the currency shock negatively affects the cross-border network and its impact on cross-border borrowings changes based on lender banks’ country origin, showing the importance of diversification of funding partners.