Barnsbury was built around 1820, as a middle-class neighbourhood, but after the Second World War (1939–1945), many people moved to the suburbs. The upper and middle classes were fleeing from the working class residents of London, made possible by the modern railway. At the war's end, the great housing demand rendered Barnsbury a place of cheap housing, where most people shared accommodation. In the late 1950s and early 1960s, people moving into the area had to finance house renovations with their money, because banks rarely financed loans for Barnsbury. Moreover, the rehabilitating spark was "The 1959 Housing Purchase and Housing Act", investing £100 million to rehabilitating old properties and infrastructure. As a result, the principal population influx occurred between 1961 and 1975; the UK Census reports that "between the years of 1961 and 1981, owner-occupation increased from 7 to 19 per cent, furnished rentals declined from 14 to 7 per cent, and unfurnished rentals declined from 61 to 6 per cent"; another example of urban gentrification is the super-gentrification, in the 1990s, of the neighboring working-class London Borough of Islington, where Prime Minister Tony Blair lived until his election in 1997. The conversion of older houses into flats emerged in the 1980s as developers saw the profits to be made. By the end of the 1980s, conversions were the single largest source of new dwellings in London.