year	# of respondents	% of respondents
2007	23	3.2%
2006	31	4.3%
2005	108	15.0%
2004	99	13.7%
2003	58	8.0%
2002	70	9.7%
2001	46	6.4%
2000	99	13.7%
1999	55	7.6%
1998	46	6.4%
1997	38	5.3%
1996	15	2.1%
1995	19	2.6%
1994	15	2.1%