In the episode where Newman is planning his New Year's Eve 2000 party "Newmallinium", Jerry bursts Newman's bubble at the end of the show. He says that since the real millennium doesn't start until 2001, his party would be "one year late, thus quite lame." In reality, if he had the party in 2000 it would be one year early, would it not?
Actually, earlier in the episode Newman says that he made his reservation at the hotel simply for "the eve of the new millennium", not 12/31/99. So you were supposed to assume that his party had been scheduled for 12/31/00, which would in fact be quite lame in the eyes of most people.
Oh man! I thought I was the only one who noticed this! Yes, I think you are right. Newman's party was going to be in 2000, the real new millennium was going to begin in 2001, so Newman's party would be one year EARLY, not one year LATE! It's so obvious!!! Great one.
The first comment is actually correct. Newman only says that he reserved the hotel for the 'new millennium' which would be 12-31-00, not 1999. Thus he would be one year late, and quite lame.
According to all computer programs in the world (circa 1900's), the new age started with the year 2000. Simply because they weren't programed to deal with four digits... i.e. 2000 as opposed to 99 (the year 1999).
This is why the big deal was made about y2k. But, you are correct, the millenium didn't start until the year 2001.
Earlier in the episode, Kramer says his party is on 12/31/99. Since Kramer and Newman's parties are on the same day, Jerry did make the mistake of saying Newman's party is one year late, instead of one year early.