While the stock market is open on Monday, banks, schools, and the bond market are closed. (Government offices, too, but they are closed all the time these days.) In past years with the bond market closed, the stock market has done quite well on Columbus Day. Of course the most famous Columbus Day rally was in 2008 when the market gained over 11% after having crashed the week before. The last few years I showed that positive momentum leading up to Columbus Day has generally led to a positive Columbus Day. Columbus Day has been celebrated on the 2nd Monday of October since 1971. Below is an updated version of the Columbus Day study.