Tony, the drop is worldwide.
Hard to say the part due to economic situation and faster F18 tendancy.
One thing is sure this performance pushing situation does not help to buy new boat.
When you said the responsability is on F18 committees, it's like to say there is a robbering and it is only police fault.

F18 replace Nacra 6.0 and Inter 18, used Tiger because of a good concept.
In 2012 the Hobie 16 was the largest numerous fleet in France.
So may be that is an answer to your question.