Although the Foundation Day of Himachal Pradesh is 15th April 1948, it became a full fledged State on 25th January 1971. Over 75 per cent of its people are engaged in agro-pastoral activities and several varieties of fruits and foodgrain are grown. Irrigation potential of the State is 3.35 lakh hectares. Mushroom cultivation, rearing sheep and cattle, breeding rabbits, pisciculture, floriculture, and fruit processing and packaging are the main occupations of the people. It is also developing herbal resources, tea gardens, wool, sericulture and electronic industries, and in the small scale sector, microscopes, watch parts, thermometers and hospital equipment are being manufactured. Forests occupy 64 per cent of its area. The State has deposits of limestone, rock salt, gypsum and silica-sand. Winters are severe and summers are cool. The average annual rainfall is 143 cm.