1988-D MD?

Your right it's a 1988-D cent. LOL Now that we've identified it, there is some Die Deterioration SE of the date. Common on zincolns. The dies have a shallower depth to them (single squeeze process) than the older multistage die setups. So we see that on your coin and others when they get to this die state.

Inder the mint mark in the same direction you can see where the plating was split during the strike and now is showing the zinc in that area.