I made a report in crystal reports and its cross tabbed with Times on top, what i need to do is be able to group the times by hour but I have no clue how to do that

right now it looks like this:

8:01 8:11 8:15 8:45 9:15 9:34 and so on

it needs to be like this
8:00 9:00 and so on having everything in the 8-9 range under 8 and 9-10 under 9 and so on

I am using a Ms sql database and taking info from a number field numbers are in the format 800 for 8 oclock 930 for 9 thirty and so on

how would I group them like this