You want to be very careful with your numbers there. For example, Cassandra doesn't really have a yearly cabaret. She does them about three or four times a year, so while the December cabaret can only happen once a year, it's not really a yearly event.
And if there were 4 dancers performing, it looks odd (to anyone in the know about the local scene) when you use the number 3 instead. It's like Cassandra herself doesn't count...