The aim of this study is to investigate the oil prices, which have crucial impact of an economy, using new ratios called Nickel ratios instead of the golden ratios on technical analysis. The Nickel ratios are developed considering Nickel Fibonacci sequence. This study is the first to use Nickel ratios in technical analysis in economics and finance. In this study, graphs comprising of weekly, daily, $4-$hour and $30-$minute periods are analyzed using Nickel ratios in Fibonacci retracement, fan, arcs and time zones applications, and the results are compared with the golden ratio obtained from the Fibonacci number sequence. In addition, the support and resistance points obtained from Nickel ratios have more significant levels than the golden ratio. The retracement, fan, arcs and time zones graphs with weekly, daily, four hourly and half-hourly data based on the golden and Nickel ratios show that the levels regarding the Nickel ratios confirm more significant points in comparison with the levels regarding the golden ratios. Finally, more efficient results are observed when the ratios of golden and Nickel are considered together.

The aim of this study is to investigate the effect of the use of derivative products on the profitability performance of banks. In the study, the effect of derivatives use of deposit and participation banks on return on assets, return on equity and net interest margin was analyzed by using the VAR Model for the 2005Q4-2020Q4 periods. According to the VAR model findings; it was observed that in the use of derivatives by deposit banks, net interest margin responded significantly against 1 standard false shock, while in the use of derivatives by participation banks, return on equity responded significantly. In the analysis of variance decomposition of deposit and participation banks, it was observed that the use of derivatives by deposit banks had the highest effect on net interest margin, then on return on assets and return on equity, respectively, while the use of derivatives in participation banks had the highest effect on return on equity. Also, with the Toda-Yamamato causality test, it was determined that there is a two-way relationship between the use of derivatives in participation banks and return on equity.