Celebratory gunfire causing injury or death - anyone know?

Does anyone know any statisics about how many people are injured or killed when the projectiles come back down from the sky? I personally think celebrating by shooting into the air is incredibly stupid, but I have heard conflicting stories. In one well publicized instance, there was a girl in the Phoenix area who was hit and killed by such a bullet while standing in her back yard talking on the phone, but I'd like to see if anyone knows of any other verifiable incidents.