STRUCTURAL ADJUSTMENT PROGRAMME AND TIME SERIES PROPERTIES OF COCOA PRODUCTION, EXPORT AND PRICES IN WEST AFRICA (1961-2007): AN APPLICATION OF THE PERRON TEST

This paper examines the structure of the West African Cocoa Agriculture by analyzing fifteen pertinent annual series, namely; acreage, yield, producer price, quantity exported and export value of cocoa, in Ghana, Nigeria and Cote d’Ivoire during the 1961- 2007 period. The methodology used is that of Perron (1989) wherein he tests the null and alternative hypotheses of a unit root or `trend-stationary` series, respectively, in the presence of possible slope and/ level shifts. The results for the Perron unit root tests indicate that all the series are trend stationary rather than being differenced stationary with the exception of cocoa export in Cote d’Ivoire and Ghana, as well as cocoa export value in Nigeria. Meanwhile cocoa producer price in Nigeria, cocoa acreage, cocoa producer price and cocoa export in Ghana alongside cocoa export value in Cote d’Ivoire were still not stationary after the introduction of the broken trend and intercept variables into the Perron model. The Perron changing growth model also revealed that SAP, otherwise referred to as structural break significantly and positively affected cocoa yield in all of Ghana, Nigeria and Cote d’Ivoire. It also has a positive and significant effect on cocoa acreage in Nigeria. While Structural Adjustment programme also have a positive and significant effect on cocoa export in the three selected countries, it did not have a positive and significant effect on cocoa producer price in all the selected countries