How to NOT draw a horizontal line at 0 for charts (Power Pivot)

[JollyRoger01]

I have an issue where the pivot charts are plotting zero values, NA values and blank values as a horizontal line. I just want a an single line starting at 10 in Dec-20 that goes to 0 at Feb-21 then back up to 100 at Sep-21. Instead I am getting a flat line with inflections at the months with non-zero values.

Power Pivot is also not using my date system and is insisting on grouping December together, so December 2020 and December are right next to each other. Obviously I want these at opposite ends of the scale like I have in my list.

Current input and output

Desired output

Anyone have any ideas?

 

[JollyRoger01]

Also (apologies for double posting) if someone could instruct me on how to edit a post on here it would be much appreciated.