23 thousand RVs were shipped in  November 2006 according to the RVIA.  Of these, 11,700 were travel trailers - about 50%.

Fifth wheels were about 5,500 (about 23%)
Motorhomes (class A) were about 2,600 (about 11%)
Motorhomes (class C) were about 1,100 (about 5%)

The total number of RVs shipped has risen in the last 4 years prior to 2005:
2002 up 21%, 2003 up 3%, 2004 up 15%, 2005 up 4%

It looks as if that trend continued in 2006 with about 367,000 RVs shipped up to November compared to about 384 in the whole of 2005.

RVIA website
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