Is it possible to add a Total percentage column to a matrix?

[jo_at_price]

I would like to add a Percent column to a matrix based on this table :

ITEM	Report Date	Events
FANS	2020-05	4
HVAC	2020-05	22
HEATERS	2020-05	21
CIRCUITS	2020-05	25
UNDEFINED	2020-05	15
HONEYCOMBS	2020-05	1
FANS	2020-06	5
HVAC	2020-06	34
HEATERS	2020-06	17
CIRCUITS	2020-06	43
UNDEFINED	2020-06	20
HONEYCOMBS	2020-06	2
HVAC	2020-07	42
GRILLS	2020-07	1
HEATERS	2020-07	25
CIRCUITS	2020-07	47
UNDEFINED	2020-07	16
HONEYCOMBS	2020-07	4
FANS	2020-08	2
HVAC	2020-08	21
GRILLS	2020-08	2
HEATERS	2020-08	13
CIRCUITS	2020-08	43
UNDEFINED	2020-08	4
HONEYCOMBS	2020-08	1
HVAC	2020-09	7
HEATERS	2020-09	7
CIRCUITS	2020-09	20
UNDEFINED	2020-09	4
HVAC	2020-09	17
HEATERS	2020-09	17
CIRCUITS	2020-09	48
UNDEFINED	2020-09	10

The matrix looks like this:

But everytime I add a percent column/measure, I get several columns, one for each of the months. I don't need that, I only need one percentage column, based on totals. And (if possible) a way to ignore the the values for 1-SEP-2020. Is it possible?

[PaulDBrown]

@jo_at_price 

You can create a "custom" structure for your columns if you want to "override" the default.

Here is an explanation on how to do it:

Creating a “custom” or “hybrid” matrix 

[lbendlin · Accepted solution]

Did you know you can use your mouse to squeeze columns to make them close to invisible?  (Requires that you disable word wrap).  That way you can "hide"  the individual percentages.

As for ignoring September - that will require a measure.

[jo_at_price]

Did not work. It does hide the percentages columns but makes the rows too tall:

[lbendlin]

Remember to disable word wrap