Thanks for your solution below, it brings me close to resolving my issue but i am still missing something. I am working on QlikSense April,2019 and running into an issue with dynamic formatting in Line chart. The expression seems to work fine in a table box though.
My user needs to cycle through 50+ extensions via a drop down and for each measure selected needs to show its trend over time on a line chart. I used an inline table and created 50 measures and in the front end i use pick match as in below example.
The number and currency format work fine , the percentage format however does not convert on the y axis. If you hover over the value points they show up in percentage format but the axis does not.
I have used your solution by creating a new field in the inline table called MetricFormat and its values are like Integer,Percentage.I then created a variable vFormat in the front end like this