Grouping Data within Excel Graph

Hello,

I have a graph that I need help with. Along the horizontal axis I have times of the day which is group by the date itself. I would like to expand the grouping up into the plot area. Not easy to explain so please find attached a test sheet.

The first graph is how it currently is, I have added purple boxes to highlight the data grouping.
The second graph is how I would like it to be, I have added red lines to highlight.

I am using MS Excel 2010


Can this be done.?
Thank you.