Social conditions that led to formation and popularity of the FIS included a population explosion in the 1960s and 70s that outstripped the stagnant economy's ability to supply jobs, housing, food and urban infrastructure to massive numbers of young in the urban areas; a collapse in price of oil, whose sale supplied 95% of Algeria's exports and 60% of the government's budget; a single-party state ostensibly based on socialism, anti-imperialism, and popular democracy but ruled by high level military and party "nomenklatura" from the east side of the country; "corruption on a grand scale"; and in response to these issues, "the most serious riots since independence" occurred in October 1988 when thousands of urban youth took control of the streets.