Raw data to Custom data in to Stacked Bar chart (Combined Y-axis | workbook attached)

I'll describe the problem a little bit: So, I have a raw data source where all the users and people, who work on that sheet enter and like modify the data.
What I have been assigned with is that:

• There are a few sheets which are named by the companies [which is a column in the data].
• Each of these sheets are formatted in a certain way where the first column is kind of merged [see the image/workbook for more reference, if you don't get it, ping me]
• My superior has requested a stacked bar chart where the products on the Y-Axis are clustered into the categories they fall into according to the various tiers. So, like T1 can have C1, C2 type and all T1 should appear first. [Again descriptive in the workbook]

The major problem lies whenever someone "adds a row somewhere in between". In that case, all the process has to be done manually, AGAIN & AGAIN like creating the data and making the chart.
I am stuck at the point where I want to automate the fact that whenever someone adds a row it automatically goes into the correct subcategory in the table and merge or whatever but the chart gets updated in the same fashion.

Any help?
Let me know if you have any questions.

Try using a pivot table and chart.

When new data is added to raw data you simple need to refresh.
I added a slicer for Company selection, but you could use the field dropdown on the chart