aggregating time while count values

Hi - good to meet everyone and thank you for your help in advance
My issues is - i would like to group the time in column c ( in 5 min intervals) and count the values in column d during those 5 minute time aggregation
so per sample data below or file attached the time between 0:00 and 03:04 would be the first 5 min and I would get a count of 7 ( the amount of 100 that occurred during that first 5 min )
what is the best way I can achieve this - thanks

site Date Time Code
4 3/18/2014 00:38.0 100
4 3/18/2014 00:46.0 100
4 3/18/2014 01:50.0 100
4 3/18/2014 02:14.0 100
4 3/18/2014 02:25.0 100
4 3/18/2014 02:37.0 100
4 3/18/2014 03:04.0 100
4 3/18/2014 05:39.0 100
4 3/18/2014 05:53.0 100
4 3/18/2014 05:58.0 100
4 3/18/2014 06:32.0 100
4 3/18/2014 13:42.0 100
4 3/18/2014 14:36.0 100
4 3/18/2014 17:06.0 100
4 3/18/2014 28:22.0 100
4 3/18/2014 28:33.0 100
4 3/18/2014 28:43.0 100