Americans send over three billion Christmas cards a year. The average American gets 10 cards a year, or 31 cards per family. If you figure that you can stack about 30 cards with their envelopes per inch, and put the whole stack together, that would be 1,578 miles (2539 kilometers) of cards. It would reach more than six times farther out into space than the International Space Station. Measure that in trees, and it works out to about 3.156 trees. Assuming some of the paper is recycled, figure 2,000 trees cut down per year to make Christmas cards, and that’s just in America.