what is a rallye dash?

I had ordered a 72 340 Duster after the 71 I had ordered never came in. When I heard 72's were doing away with Rally dash and lowered compression I balked at the order. Eventually I found the 71 340 I had ordered at a different dealer and bought it. Unfortunately I sold it in 1980 after our third gas crisis and the price had jumped to 50 cents a gallon.