The seventh day of the first lunar month in 1972. According to the China Knowledge Network, February 21, 1972 on the lunar calendar was the seventh day of the first lunar month in 1972, Renzi, the Year of the Rat. The lunar calendar for February 21, 1972: the seventh and eighth days of the first lunar month of 1972: Renzi Renyin Renwu Five elements: water, water, water, wood, water.