Agriculture was able to expand during the 1960s and 1970s as it had access to new land and unemployed labour. Between 1962 and 1983, the agricultural sector grew by 4.1% a year on average and in 1980 it employed over 70% of the working population. Yet, the state perceived developments in the agricultural sector as necessary for industrialization and exports were taxed in order to keep domestic prices low and raise revenue for state investment in other areas of the economy.