Microsoft Access - Using Concat related on a field with a compound key

Question

I am working on trying to use Allen Browns ConcatRelated() method (http://allenbrowne.com/func-concat.html) on a table in the following format:

[id1 | id2 | id3 | id4 | id5 | otherfield | year]

where id1 to id5 are the fields I need matching to concatenate years on.

For example:

1|2|3|4|5|abc|2017
1|2|3|4|5|abc|2018

should become

1|2|3|4|5|abc|2017,2018

I have used Concatrelated in the past but I am unsure of what to do when the key is made up multiple attributes.

Thanks, and sorry if my description is unclear