Iran today is running short of water. Of the nation's 31 provinces, only two have maintained the balance between water use and renewal of water resources. One of the driest countries in the world, Iran needs a minimum of 251 millimeters of annual rainfall to avoid rapid desertification. Iran's water crisis has also led to loss or salinization of topsoil and land subsidence in 25 provinces. By 2019, agriculture accounted for between 60 and 80 percent of Iran's water consumption but provided only 18 percent of the gross domestic product.