Can you help please?
Looking for expression to count the Ref ID from those ClientID who appear in 2017 only leaving out those who appear in both years.
The result coming form below example should be 3 as D and E appears only in 2017. Any ideas please?
Let's assume that we only want to work with only 2017; we have years from 2000 to 2017, it won't be pleasant to write all the years as you did in your expression (which works by the way)
How should we tell sense to only count those who have Only(year) = 2017?