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CCFC
Final season at HR was an averages of 16,046, the highest for several seasons. The highest in recent memory was the BR days which hit just over 20K average.
2005/06 21,302
2006/07 20,342
2007/08 19,123
2008/09 17,408
2009/10 17,305
2010/11 16,409
2011/12 15,118
2012/13 10,906
2013/14 N/A
2014/15 9,332
2015/16 12,543
WASPS
There’s no specific attendances available for prior to the move to Loftus Road however you only need to look at images of the ground at Sudbury to see they would struggle to fit more than 1K in, if that.
Interestingly in the process of checking these stats found out that prior to getting an ownership stake in Loftus Road they had already purchased land for a new ground in London. They abandoned those plans to move to Loftus Road.
Loftus Road
1996/97 5,800
1997/98 5,834
1998/99 5,495
1999/00 4,918
2000/01 5,671
2001/02 5,861
Wycombe
2002/03 9,921
2003/04 7,731
2004/05 8,756
2005/06 11,370
2006/07 8,278
2007/08 11,421
2008/09 9,310
2009/10 18,616
2010/11 16,756
2011/12 6,745
2012/13 11,786
2013/14 13,972
2014/15 6,295
Ricoh
2014/15 19,911
2015/16 14,866
LONDON WELSH
Highest attendance season before their move was 4,400. Regularly had attendances of under 1K
2012/13 5,090
2013/14 1,723 (Championship)
2014/15 3,319
This season they have moved back to London.
LONDON IRISH
Final season before their move the average was 4,370, there was no significant difference from previous seasons.
2000/01 5,920
2001/02 6,927
2002/03 9,921
2003/04 10,657
2004/05 14,010
2005/06 10,956
2006/07 14,828
2007/08 9,950
2008/09 15,084
2009/10 13,394
2010/11 16,227
2011/12 14,340
2012/13 9,471
2013/14 14,096
2014/15 13,236
2015/16 12,115
Their new owner have expressed a desire to return the club to London. They have already built a huge new training facility and club offices in London.