Accumulated percentages in line chart - part 2

[#1]

Dear all

Last week I got help to accumulated percentages in a line chart (http://community.qlik.com/message/377395#377395), but I've been told to redo the chart slightly. So here is part 2 of the question

Original question:

I wan't to follow student dropout ratio in the first year of their study in a line chart. 1.9.2012 4.969 students started on a bachelors degree at the University. From my data I can see their study status (active or dropout) and if they are dropouts, I can see on which date they left the University.

The right answer to this was: count({<Educational_status={'Dropout'}>}Student_id)/ count(total Student_id)

but now I've been told to have last years dropout on the chart as well (appr. 4.500 students enrolled in 2011). The chart with numbers looks something like this:

However I can't figure out how to show the accumulated percentage of dropouts vs. the entire population each year (4.969 students in 2012 and appr. 4.500 in 2011). When I use your expression on a chart with both years, the percentages are halved (propably because of the "total student_id" I guess). The Year are a new variable and for dropoutdate for students who where enrolled in 2011, I used the dropoutdate+365 days so 2011 and 2012 would come out on the same chart.

Can this be done relatively easy?

I've attached an excel version of my data if this could be usefull.

Can anyone help me?

Thanks in advance

Cheers

Bruno

[#2 · Accepted solution]

Here, where you count the total students:

count(total Student_id)

You could add a dimension to the TOTAL clause:

Count(TOTAL<Year> Student_id)     // Here I assume that your Year field is called 'Year'.

This way, the expression will count separately the students for 2011 and for 2012, as it will still use the Year dimension.

[#3]

Thanks a lot - worked perfectly

And nice explanation too.

Cheers

Bruno