Thanks to the turbulent six-year administration of Eduardo Frei (Populist Capitalist Party), the struggling working class in Chile cast their votes for change and elected communist Salvador Allende in 1970. The failures of President Allende's government, and an unwillingness of the wealthy class to work cooperatively with it, resulted in a runaway inflation rate in 1973 and numerous strikes throughout the country. The sheer number of strikes occurring during that time exerted a major impact on the economy. The Movimiento Izquierda Revolucionario (MIR), who were influenced by Che Guevara's ideas, and Partido Socialista Chilena (PSCh), had unsuccessfully attempted two previous coups, the last of which was on June 29, 1973. They went underground. On September 11, 1973, a CIA-backed military coup overthrew President Allende and installed General Augusto Pinochet as president. Pinochet's regime committed some serious human rights violations during his first years in power and was later voted out of office after a full eight-year term. Due to revelations that President Richard Nixon ordered the CIA to "make the economy scream" in Chile to "prevent Allende from coming to power or to unseat him," a major Senate investigation was launched in the mid-1970s. Newly declassified documentation shows attempts by the CIA, National Security Council, and President Frei, to prevent President-elect Allende's inauguration and to "destabilize" the Chilean economy prior to the military coup. In addition, DINA (Chilean secret police) and the CIA participated in a state-sponsored terrorist campaign called Operation Condor, during that time.