I've found lots of stuff on this for QV (surely it can't be that hard to do one of the most common requirements?!).
What I need is an expression for QlikSense that counts the number of clients making up the top 80% so that I can use the 'limit' option (I think). I have been working with RangeSum() & RangeCount() but as soon as you introduce these into a table the sort reverts to Client ascending. e.g. RangeSum( top(sum(Revenue),1,RowNo()) )
I don't think this is possible unless your clients are loaded in order of revenue total in the script. The aggr function doesn't have an option to sort the virtual table it creates. And the Limit option in Qlik Sense is rather limited and doesn't have a 'Show only values that accumulate to' like Qlikview has. You'll have to do something like explained in this blog post and manually count the clients: Recipe for a Pareto Analysis