It should however be kept in mind that it only gives insights into quantitative aspects of water resources and that a national level indicator may hide significant territorial and seasonal differences and should be complemented with information at sub-national level. This indicator should be read in connection with other environmental indicators and in particular with indicators on water supply prices, cost recovery ratios, water productivity and water quality. This is particularly important for countries with larger territories where resources are unevenly distributed. In the the 1980s, some countries have stabilised their abstractions through more efficient irrigation techniques, the decline of water intensive industries (e.g. mining, steel), increased use of cleaner production technologies and reduced losses in pipe networks. Agriculture remains the largest user of water worldwide, with an increase in global abstractions for irrigation by over 60% since i960. Most countries continue however to face seasonal or local water quantity problems and several countries have extensive arid or semi-arid regions where water is a constraint to economic development.