NET INTEREST MARGIN DYNAMICS IN THE TURKISH BANKING SECTOR UNDER HIGH INFLATION

Öz

This study analyses net interest margin dynamics in the Turkish banking sector under high inflation and elevated interest rates. Contrary to conventional expectations that rising rates widen margins, empirical evidence shows that net interest margin has contracted. Policy rate increases exert a negative long run effect, while higher non performing loans further compress profitability. A positive relationship has been found between capital adequacy and net interest margin. Short deposit maturities cause funding costs to adjust faster than lending rates, exposing banks to interest rate risk. Macroprudential measures—such as reserve requirements, security holding obligations, and credit growth restrictions—reduce asset liability flexibility, amplifying downward pressure on margins. High volatility in inflation and policy rates is complicating margin management. As a result, real returns on equity erode despite nominal profits, creating hidden profitability risks. The findings highlight the need for durable price stability and balanced regulatory design to sustain banking resilience and long term profitability.

Anahtar Kelimeler

• Net Interest Margin
• Inflation
• Capital Adequacy
• Non-Performing Loans
• Profitability

YÜKSEK ENFLASYON ORTAMINDA TÜRK BANKACILIK SEKTÖRÜNDE NET FAİZ MARJININ DİNAMİKLERİ

Öz

Bu çalışma, yüksek enflasyon ve yükselen faiz oranları koşullarında Türk bankacılık sektöründe net faiz marjı dinamiklerini incelemektedir. Artan faiz oranlarının marjları genişletmesi yönündeki klasik beklentilerin aksine, ampirik bulgular net faiz marjının daraldığını göstermektedir. Politika faizindeki artışlar uzun vadede olumsuz etki yaratırken, artan takipteki krediler rasyosu kârlılığı daha da baskılamaktadır. Sermaye yeterliliği ile net faiz marjı arasında pozitif yönlü ilişki tespit edilmiştir. Mevduatın kısa vadeli yapısı, fonlama maliyetlerinin kredi faizlerinden daha hızlı uyum sağlamasına yol açmakta, bu da bankaları faiz riskine maruz bırakmaktadır. Zorunlu karşılıklar, menkul kıymet tesis yükümlülükleri ve kredi büyümesine yönelik sınırlamalar gibi makro ihtiyati önlemler, aktif pasif esnekliğini azaltarak marjlar üzerindeki baskıyı artırmaktadır. Enflasyon ve politika faizlerindeki yüksek oynaklık, marj yönetimini daha da zorlaştırmaktadır. Sonuç olarak, nominal kârlar korunuyor gibi görünse de özkaynakların reel getirisi aşınmakta ve gizli bir kârlılık erozyonu ortaya çıkmaktadır. Bulgular, bankacılık sektörünün dayanıklılığını ve uzun vadeli kârlılığını sürdürebilmesi için kalıcı fiyat istikrarı ile dengeli bir düzenleyici çerçevenin önemini vurgulamaktadır.

Anahtar Kelimeler

• Net Faiz Marjı
• Enflasyon
• Sermaye Yeterliliği
• Takipteki Alacaklar
• Karlılık

Kaynakça

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