A study also shows that rural-to-urban area migrants have a higher standard of living than both non-migrants in rural areas and non-migrants in urban areas. This results in changes to economic structures. In 1985, agriculture made up 37.2% of Vietnam's GDP; in 2008, that number had declined to 18.5%. In 1985, industry made up only 26.2% of Vietnam's GDP; by 2008, that number had increased to 43.2%. Urbanisation also helps to improve basic services which increase people's standards of living. Access to electricity grew from 14% of total households with electricity in 1993 to above 96% in 2009. In terms of access to fresh water, data from 65 utility companies shows that only 12% of households in the area covered by them had access to the water network in 2002; by 2007, more than 70% of the population was connected. Though urbanisation has many benefits, it has some drawbacks since it creates more traffic, and air and water pollution.