Who do I blame for this?

According to the New York Times, Michael Ondaatje won the "Golden Man Booker Prize" for his 1992 novel The English Patient. The Golden Man Booker Prize is like a souped-up version of the annual award: five judges were asked to choose the best winner from each decade, and then the public voted on the resulting shortlist of nominees. Someone clearly got it wrong, but I'm not sure who: I feel strongly that the best Man Booker winner is A.S. Byatt's 1990 book Possession, but does that count as the end of the 80s or the beginning of the 90s?