How does this data pattern fit with your explanation? [pre]01/13/11 14:31:49 16.54 16.53 16.55 0 01/13/11 14:31:55 16.54 16.54 16.54 1232 01/13/11 14:33:05 16.54 16.54 16.54 25 01/13/11 14:33:20 16.54 16.54 16.54 25 01/13/11 14:33:40 16.54 16.54 16.54 25 01/13/11 14:33:55 16.54 16.54 16.54 25 01/13/11 14:33:57 16.54 16.53 16.55 -1232 01/13/11 14:35:09 16.5499 16.53 16.55 400 01/13/11 14:35:13 16.55 16.53 16.55 700 01/13/11 14:35:32 16.5305 16.53 16.55 100 01/13/11 14:35:32 16.531 16.53 16.55 100 01/13/11 14:35:32 16.531 16.53 16.55 200 01/13/11 14:35:32 16.531 16.53 16.55 100 01/13/11 14:35:42 16.53 16.53 16.55 100 [/pre]