Leifmk
Deity
*In before someone points out that the '80's didn't start until 1981*
Um, but the 80s did start in 1980, as they are the decade numbered as 1980-something. If we were talking about "the 199th decade" it would be another matter but nobody's talking about that. (In many parts of the world it is also usual to speak of centuries as, for example, "the nineteen hundreds" instead of or alongside "the twentieth century" -- those two terms each define a 100-year period, but not exactly the same one, as "the nineteen hundreds" indeed begins with the year 1900 and ends with 1999.)