For a Summary Table, BoxPlot and aggregation the Statistical Measures dialogue allows me to select P90 (90th Percentile), along with all the other stats such as Median, Avg, Min, etc. I would like to be able to add P95 (95th Percentile). I know there is a function called Percentile(arg1, arg2) that can calculate this, so if I can create a new Statistical Measure called 'P95' which represents "Percentile(<data set>, 95.0)".
Similar, I'd like to define e.g. the relative standard deviation. It's possible to show the std and the mean but I'd like to show the ratio of those two.