Using an analysis of tokens from the 1996 LA Times and New York Times corpora, this article claims that there are five factors included in reading 'the last/next + decade/century': tense, prepositions, other lexical clues, relevance to the utterance time and pragmatic world knowledge. The study additionally questionned educated native speakers of American English. The findings support the aforementioned results and also disclose that native speakers do not accord on what preposition to employ for which interpretation.