Why did Mopar make so many green cars?

I sold a 69 road runner to .a friend of mine back in 1983. I then restored the car for him with a unlimited budget. Car was F-8 and was repainted the same color. Turned out very nice. He entered it in a lot of car shows but it never could pull off a 1st place. We then took the car completely apart, painted it Lemon twist Yellow, this was the only change. Car won best of show at almost every show it was entered. Color does matter.