 And I thought, I'm done with algebra. But when I got in basic training in the National Guard, they used an engineer's map and a compass. And the engineer's maps are printed. They don't print them year in, year out. But at the bottom of the page, the instructor's saying, you'll look down at the bottom of the page, you'll see a formula where you need to adjust the reading on the map based on the year this map was printed. I looked down, and guess what it was?