Calculate defects separated with comma? Need urgent help please

Hi All,
I've been trying to find a solution for my issue but despite multiple attempts I have failed.
After about a month and a half of persistent failures, I've decided to ask you good people for help :-)

I did managed to find a solution that works but it has one major limitation which I cannot live with ;-)
Ok so he's what I'm trying to do:
Attached is a sample data containing records for product testing, you'll see bunch of columns but the ones I'm interested in are:Location, Date Collected, BUName,Mastercode,Fail Reason.
Here's the catch, Fail Reason has 1 or more defect in the same cell separated by comma, what I need is a pivot table or something similar that would count percentage of defects (Fail Reasons) per product, my current solution does this but the way it is built it prevents from using filter on date and this is that one major limitation.

I haven't probably explained this properly, All I need is the ability to somehow calculate percentage of defects per product and use remaining fields as means of filtering.

Thank You

Thank You both for taking your time to help me out, really appreciate this.
FDibbins you are absolutely correct, fail reasons are defined in another table. Reason for "G10=Heavy rust marks identified. This arrival was quality sorted" and other inconsistent records comes from earlier version of the system where fail reason field was a free text but now it has drop down boxes with predifined list of defects.
There are currently total of 45 defect in my table and these are the only ones calculations should be run on (anything else that's not in defect table should not be taken into consideration)
I'd like to be able add more defect in the future and I'm sure as the system grows this will indeed be the case.
Defects:
rot
mould
sprouting
external re-growth
greening
Internal Browning
Gel breakdown
waste
Shrivel
Sunken lesion
Stem End Rot
Speckling
Hard Rot
Internal defects
Waste
soft/ spongy
collapsed fruit
Bruising
Rots
Mouldy Crowns
Overmature
Rotten Crown
Mealy bug
heavy rusk marks
Spots
Internal brownig
Black Spots
BLACK SPOT
Pest Damage
Internal Damage
Splits
Slipskin
Running juices
Dead berries
Waterberries
Bladdery
rots/mould
PSD
Pitting
Collapsing rot
Shrivelled/dehydrated fruit
RBD
Blind waste
SERB
Degreening Burn

Thank You