Data and Time manipulation

Hi,

I followed your instructions and have created a time table, this allows me to allocate a time slot to production. I can then graph this, however what this doesn't show me is the points of zero production.

For example if i plot the below data it will not show 0 for the 30 minute slots between 12:30 and 1:30 and i would like to sum every time slot between 7am and 7 pm and display zero where no production: 

Thanks