I got a similar issue.
Same search engine traffic for well over a year now, used to convert in less than 1/80 last year and most of this year. Now it's mysteriously just gone to a lot 0.00s this period.
Program, Campaign
09/07/2008 188 107 4 3 1:35 0 0.00 $105.00
09/08/2008 172 113 6 2 1:56 0 0.00 $70.00
09/09/2008 193 115 3 0 0:115 0 0.00 $35.00
09/10/2008 144 83 6 1 1:83 1 0.00 $35.00
09/11/2008 174 108 3 0 0:108 0 0.00 $0.00
09/12/2008 197 111 2 0 0:111 0 0.00 $35.00
09/13/2008 165 110 4 0 0:110 0 0.00 $70.00
09/14/2008 194 121 4 1 1:121 0 0.00 $49.93
09/15/2008 181 120 3 2 1:60 0 0.00 $70.00
09/16/2008 221 134 6 1 1:134 0 0.00 $35.00
09/17/2008 252 129 6 1 1:129 0 0.00 $35.00
09/18/2008 182 106 6 2 1:53 1 0.00 $54.14
09/19/2008 174 94 5 0 0:94 1 0.00 $0.00
09/20/2008 165 100 3 0 0:100 0 0.00 $35.00
09/21/2008 179 106 3 1 1:106 0 0.00 $35.00
09/22/2008 245 129 6 1 1:129 0 0.00 $35.00
09/23/2008 211 136 6 0 0:136 0 0.00 $35.00
09/24/2008 177 103 3 5 1:20 0 0.00 $175.00
09/25/2008 216 120 7 2 1:60 0 0.00 $70.00
09/26/2008 213 124 5 0 0:124 0 0.00 $70.00
09/27/2008 295 167 9 0 0:167 0 0.00 $70.00
09/28/2008 213 124 2 1 1:124 0 0.00 $35.00
09/29/2008 151 92 4 1 1:92 0 0.00 $35.00
09/30/2008 166 110 8 0 0:110 0 0.00 $0.00
10/01/2008 165 95 5 0 0:95 0 0.00 $0.00
10/02/2008 174 98 2 0 0:98 0 0.00 $0.00
10/03/2008 164 109 2 1 1:109 0 0.00 $0.00
10/04/2008 153 96 4 2 1:48 0 0.00 $70.00
10/05/2008 164 94 5 0 0:94 0 0.00 $0.00
10/06/2008 199 107 5 1 1:107 0 0.00 $0.00
10/07/2008 156 110 9 2 1:55 0 0.00 $70.00
10/08/2008 186 130 6 1 1:130 0 0.00 $0.00
10/09/2008 188 118 6 0 0:118 0 0.00 $0.00
10/10/2008 189 115 3 1 1:115 0 0.00 $0.00
10/11/2008 231 122 4 0 0:122 0 0.00 $0.00
10/12/2008 223 138 6 0 0:138 0 0.00 $0.00
10/13/2008 218 123 2 0 0:123 0 0.00 $0.00
10/14/2008 11 9 0 0 0:9 0 0.00 $0.00