Time Series Analysis Of Quarterly Gross Domestic Product Of Nigeria:- Bernard, Chimankpam B.

ABSTRACT

The gross domestic product (GDP), a basic measure of an economy's economic performance, is the market value of all final goods and services produced within the borders ofa nation in a year. In this paper, the features of quarterly data of Nigerian GDP obtained from aggregated annual data of the National Bureau of Statistics ofNigeria startingfrom 1990 to 2012 was studied. The major objective of the study is to construct a suitable time series model which could be used to predict a reliable and dependable forecast ofgross domestic product ofNigeria. The data usedforthis project was a quarterly data collectedfrom National Bureau ofstatistics ofNigeria. The data spanned the period oftwenty-three years (January 1990 — December 2012). The time series plots of the Nigerian gross domestic product and its associated autocorrelation junction and partial autocorrelation function plots showed that the data has trend and regular seasonal pattern. The data was differenced to make itstationary. The time series analysis was done using Box and Jenkins iterative procedure. The ACF and PACF plots ofthe differenced series suggested a seasonal model. SARIMA (1, 1,1) *(1, 1, 1)4 model wasfitted. The model has been shown to be adequate.