During the second half of the 20th century Danish agriculture has experienced large-scale changes. The agricultural profession has been highly mechanized and Denmark has experienced an extensive movement of people from the rural areas to the cities. The cultivated area and the number of farms have been reduced and so has the number of employees, but the grand total of agricultural production has risen. A development which has been highly supported by information technology starting with punched cards in the 1950s and later resulting in a very efficient Danish agricultural sector, being the largest export sector in Denmark.