This thesis work has been undertaken as a partial fulfillment for the award of MSc. Degree in Development Economics at Adama University. Its accomplishment was made possible by the great effort of my adviser, Jemma Haji (PhD), a professor of economics at Haromaya University.It has also passed the official defense examination held in October 2011 at Adama University. Despite the difficulties of obtaining related time series data from Wonji Shoa Sugar factory, I have used the maximum possible effort to come out with the most important economic variables determining the production performance, measured in this thesis by yearly production of plantation white sugar. The data for most of the variables has been computed from the quarterly reports found at various production units of the factory.