New Year’s Eve isn’t a federal holiday, so why are some people surprised they have to work Friday? It’s because New Year’s Day—which is a federal holiday—falls on Saturday this year. When a holiday falls on the weekend, it’s almost always observed depending on which day it lands. If the holiday is on Saturday, it’s observed on the Friday before, and if it’s on Sunday, the holiday is observed on the Monday after. That’s not the case for Wall Street this year because of a technicality in the New York Stock Exchange Rules. “When a holiday observed by the Exchange falls on a Saturday, the Exchange will not be open for business on the preceding Friday and when any holiday observed by the Exchange falls on a Sunday, the Exchange will not be open for business on the succeeding Monday, unless unusual business conditions exist, such as the ending of a monthly or yearly accounting …