Nepal used to be an agricultural country until 1950. Since 1951 it entered the modern era and has made progress. Agriculture, however is still a major economic activity, employing 80% of the population and providing 37% of GDP. Only about 20% of the total area is cultivable; another 33% is forested; most of the rest is mountainous. Rice and wheat are the main food crops. The lowland Terai region produces an agricultural surplus, part of which supplies the food-deficient hill areas.