Creating a Cell reference counter

Good morning everyone,

Im a bit stuck on this.

I have a spreadsheet that id like to make a counter based on specific Value.

I have some text values in cells A5 B5 and C5 and i want a counter in D5. (this would then continue on for D6, D7, D8 and so on....)

So if three people have contacted me about this i want to be able to put their names in and put D5 next to them.
This will then show '3' in cell D5

I'd hopefully like to achieve this over two different sheets.
Sheet 1 is my 'issue' sheet
Sheet 2 is my 'Data Validation' sheet


So:

Joe Bloggs D5
John Smith D5
Andy Jones D5

and in the spreadsheet on Tab 1, D5 will show '3'

Sorry about the poor way of describing :O

sorry no can do, its for my work

good point.

here is one ive created
Example.xlsx

Thankyou