**4. Method of data collection**

The data used in this study is a secondary data that was collected from www.ca shcraft.com under stock trend and analysis. Daily stock price was collected on Zenith bank stock price from October 21st 2004 to May 8th 2017.

The returns was calculated using the formula below

$$R\_t = \ln P\_t - \ln P\_{t-1} \tag{29}$$

**Figure 2.**

**Figure 1.**

*The time plot of the log of zenith Bank returns.*

*Financial Time Series Analysis via Backtesting Approach*

*DOI: http://dx.doi.org/10.5772/intechopen.94112*

**Unit root testing**

**ARCH test**

**Table 1.**

**111**

*The time plot of the removal of possible outliers in the log of zenith Bank returns.*

**Statistic Value** Mean 0.000114 Median 0.000000 Maximum 0.338000 Minimum 0.405850 Std. Dev. 0.027600 Skewness 1.267452 Kurtosis 33.76662 Jarque-Bera 121905.9 (p = 0.00000)

Number of Observation 3070

*Descriptive statistics and unit root testing of zenith Bank stock returns.*

ADF 47.11172 (p = 0.0000) DF-GLS 1.842682 PP 46.52078 (p = 0.0000)

Chi-squared = 123.05, df = 12, p-value <2.2e-16

Where Rt is stock returns; Pt is the present stock price; Pt-1 is the previous stock price and ln is the natural logarithm transformation. Then total observation becomes 3070.
