Dale Irby is a creature of habit. The Dallas P.E. teacher wore the exact same polyester shirt and knit sweater vest for the past 40 years of yearbook photos.

Because Irby's retired, the 2012-2013 Prestonwood Elementary School yearbook marks the outfit's final appearance. Irby's work wardrobe consisted mainly of athletic clothes.

He chose the shirt and sweater combo for his first yearbook photo in 1973. The following year, he accidentally repeated the outfit. Irby says he was embarrassed when he got the school pictures back that second year. His wife dared him to repeat the outfit for his third yearbook photo. After that he thought, "Why stop?" Check out the time-lapse slideshow.