Consistently influential behind the scenes during Deng's time as paramount leader were fellow elder statesmen Chen Yun and Li Xiannian. Other prominent elders were Ye Jianying (until his death in 1986), Deng Yingchao (Zhou Enlai's widow, until her death in 1992) and Peng Zhen (who retired in 1988). Yang Shangkun played a brief but important role in the period between 1989 and 1992, when as President he subverted the existing constitutional convention and turned the office of President from a symbolic role into an executive one.