Complex sentence: This is a list of supercentenarians who died in the 1980s, as assessed by the Gerontology Research Group (GRG) who report 151, of whom 138 are female and 13 are male.
Split into simpler sentences: This is a list of supercentenarians who died in the 1980s. One source of lifespans is the Gerontology Research Group (GRG) who report 151, of whom 138 are female and 13 are male.