December 17, 2018 4:55 pm Monday Was Busiest Day For USPS With Christmas just a week away, Monday was the busiest day of the year for the United States Postal Service. US & World Videos 1:42 Car sent flying into the air after speeding through rotary in Massachusetts 0:28 A Vermont state trooper plunges into icy pond to rescue 8-year-old girl 2:59 Keep these travel etiquette tips in mind this holiday season 2:31 Synchronized swimmers: See an incredible triple whale breach 2:20 Bodies of Missing Men Found in Rubber Bins Inside Storage Unit