Odd Service number on WW1 British Trio

[CampX]

Well sometime ago I bought a pile of Medals Badges ect, I was after one piece in the lot, a Georgian Horse piece, one I have never seen before, and after showing to many that know more about that sort of thing than I, no one of them can ID it...however
In the stuff I bought were a couple of WW1 British Trios, as I do not collect them I listed them this morning online.

When I was doing that I noticed that the Trio to the E. York Regt. had a very odd Service number, one I have never seen before.
the Number is 10-1044, has anyone seen this type of number before, and if so why is there a - in the number? All 3 Medals are numbered this way.

Thank you in Advance

Dean O
Canada

[Jerry B]

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[Jerry B]

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[Jerry B]

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[CampX]

Thank you guys. As I said, I have never seen this - on Canadian Medals and I know very little about British ones.

Thank you again

Dean O
Canada

[Jerry B]

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[CampX]

You Guys!!! well a couple of people replied so I did not want others to feel bad if I picked you out!!! LOL

Thanks again Doug, I see why that was done, however I have had British Medals to other Units that had more than one Battn, and the numbers are not like that, so I am thinking it was not always done that way.
By the way, stick to your German stuff, you are not allowed to know about more than one type of military stuff as you make the rest of us look bad!!!!! LOL.

Take Care

Dean O
Canada