Pivot table to exclude 0's

in the attached spreadsheet im trying to create 2 graphs from the data under the HOURS tab.

Basically i need to sort the data by TEAM's. 1 graph needs to be a line graph which will graph the date (B column) and the comparison (L column). the other graph needs to be a bar chart showing the average In my example i used a pivot table to sort the data (which is under the DASHBOARD tab). The problems i have are the following:

1. i cant get the line graph to not plot 0's. In the example there are 0's for some teams on certain dates while others have values. I just want the line that has a date and value to plot
2. if i add more data how will the pivot table update? it does not seam to update automatically. is there a way to do this?