Banka Maliyetleri ve Maliyet Ekonomileri : Türk bankacılık sektörü için bir uygulama

Abstract

Bu çalışmanın amacı, bankacılık sektörünün maliyetleri ve maliyet ekonomilerinin neler olduğu konusunun analizini yapmaktır. Bu analiz 1988-1995 döneminde Türk bankacılık sektörüne uygulanmaktadır. Maliyet ekonomileri, bankaların ulaşmak istedikleri ideal büyüklüğü tespit eden ölçek ekonomileri ve bankaların çok ürünlü doğasından kaynaklanan maliyet avantaj mı ölçen kapsam (scope) ekonomilerini içermektedir. Öncelikle, bankaların toplam maliyetlerini (işletme giderlerini) hesaplayabilmek için çıktılarının neler olduğu konusunda karar vermek gerekmektedir. Bu çalışmada banka çıktıları üç aşamalı olarak ele alınmıştır; her aşama ise değişik bir çıktı kümesini temsil etmektedir. Banka maliyetleri, üç ayrı banka modeli ile açıklanmıştır. Banka modeli ile kastedilen, banka maliyetlerinin, çıktılar ile ifade edildiği maliyet fonksiyonlarıdır. Ölçek ekonomileri ile ilgili bulgular şu şekildedir: İlk bulgu, Türk bankacılık sektörünün maliyet eğrilerinin "U" şeklinde olduğunun ve ölçek ekonomilerinin varlığının kanıtlanmasıdır. Küçük ölçekli ve büyük ölçekli bankalar birbirleri ile karşılaştırıldığı zaman ölçek ekonomilerine göre küçük bankaların maliyet avantajı büyüklere göre çok daha fazladır. Kapsam ekonomileri, birden fazla ürün üreten firmaların, çıktılarının hacimlerini teker teker değil de aynı anda arttırarak maliyet avantajı elde etme kaabiliyetlerini göstermektedir. Tüm yıllar için, sektörün kapsam ekonomileri pozitiftir, yani Türk bankacılık sektörü, ürün bileşenindeki ürünlerin hacmini aym anda arttırarak maliyet avantajı elde etmiştir, öte yandan küçük bankalar büyük ölçekli bankalara göre maliyet avantaj ma sahiptirler. Kamu ve özel sermayeli bankaların ölçek ekonomilerine baktığımızda 1988- 1995 dönemindeki tüm yıllar için, kamu bankalarının genelde maliyet avantajı elde etmek için ölçek artırma şanslarının kalmadığını göstermektedir. Kapsam ekonomileri açısından bulgular, özel bankaların ürün çeşitliliklerini ve bunların hacimlerini aym anda artırarak, maliyet avantaj mı, kamusal sermayeli bankalara göre daha fazla elde ettiklerini göstermektedir.

Cost economies and bank efficiency are issues that especially concern bank executives, shareholders, policy makers, but more importantly, bank clients. Aggressive competition in the sector is forcing bank executives to make their banks more profitable through increased efficiency, while at the same time fulfilling the main goal of shareholders- increased profits. Policy makers are also regulating the market in accordance with the costs and efficiencies involved in the sector. Finally, the reduced costs and increased efficiency of a bank will have a positive effect on the quality of service rendered while reducing the cost to clients. The main purpose of this research has been to analyze the costs and cost economies involved in the banking sector and more importantly, apply this analysis to the Turkish banking sector. Cost economies consist of scale economies, which determine the optimum size that banks should reach; and scope economies, which measure the advantages gained through the multi-product nature of banks. In order to calculate the total cost (operating expense) of banks, we have to determine what the outputs are. In this research, outputs have been discussed in three phases, in which each phase is represented by a different category. The reasoning behind this is due to the fact that outputs produced by a bank can appear as an asset, as a liability, or on both sides of the balance sheet at the same time. Outputs appearing under liabilities are deposits and non-deposit funds, where loans and marketable securities appear under assets. Outputs that can be characterized as both an asset and liability at the same time are loans and deposits. Bank costs have been illustrated using three different bank models. These models are cost functions for which we can determine the bank cost by using the bank's outputs. Cost functions are derived from production functions that illustrate the relationship between input and output. A quadratic translog function that has been derived from the Cobb-Douglas production function has been used in this research. Three cost models were developed for each of the three phases mentioned earlier and later tested with data representing the Turkish banking sector for each year between 1988 - 1995. In all three of the models, operating expenses (expense before interest and taxes) are dependent variables, where bank outputs are independent variables. The outputs for the first model are deposits and non-deposit funds, for the second model are loans and marketable securities; and for the third model are deposits and loans. All twenty four cost functions utilizing multiple regression analysis and representing eight years of data are statistically significant, with R values above 90 %. At the same time, each model's F value is significant to reject the null hypothesis at even 1 % of significance level. This means that, all coefficients in each of the models are values other than zero, thus proving statistical significance. One of the most important points we notice in these findings is the great similarity of the conclusions drawn from all three models. At the same time, output coefficients being used as parameters in these models also have to be statistically significant because they are important in the calculation of cost economies. The t values in almost all of the parameters are significant at even 1 % level (coefficient value being other than zero). VI Therefore, the data of all three models as a whole, as well as its parameters, are statistically suitable to estimate the bank costs and related cost economies. Using these models we will be able to estimate Turkish banks costs by using banks outputs. Some of the most important findings that have been obtained through the use of scale economies are as follows: First, these findings have proven that cost curves in the banking sector are "U" shaped. This "U" shaped cost curve illustrates that banks have a cost advantage up to a certain point (defined as increasing scale returns); reach an optimum size at one point; and then later lose the cost advantage if they continue to grow (defined as decreasing scale returns). "U" curves have been observed for every year of the eight year Turkish banking study, the only change being the increase in optimum bank size with each passing year. Between the years of 1988-1992, the optimum bank size is determined by a deposit size of USD 500 million. We can deduce that between the mentioned period, smaller banks will benefit from a cost advantage until their deposits grow to USD 500 million, meaning that they will have increasing scale economies (it has been statistically proven in this research that smaller banks have scale economies of less than 1, where as banks with deposits of more than USD 500 million have scale economies values greater than 1.) Between the years of 1993-1995, the optimum bank size has increased from USD 500 million a period earlier to USD 1 billion, showing the overall improved cost efficiency observed in the sector. We feel that increased competition plays the most important role in this development, thus forcing banks to become more cost conscious and pay closer attention to cost efficiency. Another factor is the utilization by banks of technological developments causing expenses to decrease and cost efficiency to increase. When we compare 1988 and 1995 data of optimum size banks, we see that the deposit sizes are USD 250 million and USD 1 billion, respectively. In comparing small and large banks according to their scale economies, we find that smaller banks have an edge over larger ones when it comes to securing cost advantages. Another important point that is valid for all eight years of data is that as deposit sizes increase, so do the scale economies, thus decreasing cost efficiency. Another indicator regarding bank cost economies is scope economies. Scope economies, mainly used for companies producing a wide range of products, show the VII cost advantage that can be obtained when outputs are jointly increased instead of one by one. In other words, expanding output by jointly producing bank services is less costly than expanding output by increasing each output one at a time. Scope economies can be expressed as either positive or negative values. Positive values represent cost advantages, while negative values show disadvantages. The greater the scope economies of a bank, the greater the cost advantage it will gain. This significant measurement used for companies producing more than one product or service was also used in evaluating Turkish banks. We can interpret the values obtained for Turkish banks by saying that scope economies of the sector are positive for all years, further showing that cost advantages have been created by jointly increasing the volume of all products in the product mix. When comparing small and large banks, we come to the following conclusions: As is the case with scale economies, small banks have an advantage over large banks regarding scope economies as well. In other words, as bank size increases scope economies decrease. This statement is valid for all values obtained for all years and all three models. In fact, for the period of 1993-1995, banks with a deposit size of USD 500 million or greater had negative values for scope economies, showing that large banks- parallel with our conclusions for scale economies- can turn their advantage to a disadvantage when increasing their product mix at the same time. As a general trend, it appears that Turkish banks are losing their scope economies advantage over a period of time. While all the banks reviewed in 1988 have positive values for scope economies; only those with a deposit size of USD 250 million and under still have positive values in 1995, the remaining banks showing negative scope economies for the same year. This situation can be explained as such: At the beginning of the reviewed period, Turkish banks had a very limited variety of products and services. As years passed, not only did banks widen their variety of products and services, but also increased their volume of services rendered, therefore decreasing their chance of gaining a cost advantage by the end of the period under review. vin The last conclusion regarding scope economies is, as in scale economies, that there is no difference between the three models that were used, meaning that the scope economies values obtained from each model are totally parallel to one another. In the last part of this research, Turkish banks have been categorized into two groups according to their a capital base: state owned banks and privately owned banks; and a comparison was made between these two groups. The same methodology used in studying the entire banking sector was applied as well to studying state owned and privately owned banks. We have started the research with the development of cost functions of this sub-groups. Quadratic translog cost functions were used for both groups (as was used for the entire sector). Three different models were utilized for state owned and privately owned banks, however, econometric analyses shows us that there is no difference in the coefficient values. In other words, it has not been statistically proven that they different. Therefore, twenty-four cost functions (three different models applied to eight years of data) have been used for this group as well. We see interesting conclusions in the scale economies of state owned and privately owned banks. The "U" shaped cost curve valid for the entire banking sector is also valid for these sub-groups. In other words, the scale economies of small state owned and privately owned banks are less than 1, where when bank size increases scale values become more than 1. Another interesting point seen for every year between 1988-1995 is that the average value for scale economies of state owned banks are greater than 1, meaning that they have decreasing scale returns. The opposite of this is true for privately owned banks where the same values are less than 1 and have increasing economies of return. This clearly illustrates that in general, state owned banks have no chance in gaining a cost advantage by way of increasing their size, while at the same time privately owned banks increase their advantage by growing larger since they have increasing returns. IX For every year in this research, there is another rule that can be applied without exception to all bank categories: "Scale economies values of state owned banks are greater than scale economies values of privately owned banks." Although scale economies can not be used as sole indicator for efficiency, it clearly demonstrates here the situation of state owned and privately owned banks. Generally looking at the trend over the years of review, we notice that scale economies of state owned banks have had a fast paced development, even faster than that of privately owned banks, until 1995 (even though this trend has not been enough to provide state owned banks with increasing scale returns). The same trend is not present in privately owned banks (this value varies between 0.70-0.80 for each year), leading us to believe that state owned banks make greater efforts to become more cost efficient and invest more in technology. When evaluating the scope economies of state owned and privately owned banks, we can conclude the following: For every year of the period under review, the scope economies values of privately owned banks are positive and greater than that of state owned banks. This shows that by jointly increasing product mix and volume, privately owned banks have a greater edge over state owned banks in obtaining cost advantages. Therefore, here we can see that privately owned banks are better in allocating funds and as a result increasing their cost efficiency. Between the years of 1992-1995, the scope economies of state owned banks are negative values illustrating that they are no longer able to benefit from cost advantages. Due to the scope of this study, the following issues especially concerning the Turkish banking sector were not discussed: sector cost efficiency, viability of banking, financial failures, efficiency and cost comparison of internal profit centers of banks, and the difference in cost structures of organizationally diverse banks. The issues mentioned above will play a significant role in continuing studies on this topic.