It’s a binary year and if you use the following date format (mmddyy) on a regular basis, you might want to slow down and double check your work. This year includes: 010110, 011010, 011110, 100110, 101010, 101110, 110110, 111010, 111110. And next year will be no exception with: 010111, 011011, 011111, 100111, 101011, 101111, 110111, ...