calculate 2 rows

[bartburg]

hello ppl,

i need the following:
i got a report with a cross table in it the measure is the total calls(ppl called).
the collums are the months and the rows are the years so u get for example
(calls)           jan
2014             20
2013             30

now i want a row under the line 2013 that shows me the differance between 2014 en 2013.
so i want it to show 10
witch function do i use for this of how can i make it  so i can see the differance.

tnx for the help !

[CognosPaul]

Is this a relational or dimensional data source?

[bartburg]

relational!

[CognosPaul]

There are a few ways of doing it.

Let's try the easy way:
Create two data items:
Current Year:  case [NS].[Time Dim].[Year] when #timestampMask($current_timestamp,'yyyy')# then [Measure] else 0 end
Previous Year: case [NS].[Time Dim].[Year] when #timestampMask(_add_years($current_timestamp,-1),'yyyy')# then [Measure] else 0 end

Create a third data item:
[Current Year] - [Previous Year]

Put that data item in your crosstab and, hopefully, it should be what you're expecting.

[bartburg]

after some trys i got to work with a part of your awnser
datepart 1(2014):
IF ([jaar]= 2014) THEN ([aantal]) ELSE ('0')
datepart 2(2013):
IF ([jaar]= 2013) THEN ([aantal]) ELSE ('0')
datepart 3 (differance):
[2014] - [2013]

but now if i look at the pivot table there is a differance of 1 per table the differance between the tables stays the same see below
                 jan              but it shows
2013           5                   6
2014           6                   7
differance    1                   1

how can the output of 2013 and 2014 be the anwser +1 and how can i Ensure that the calculation is correct?

[CognosPaul]

Is the aggregation method count or count distinct? use ELSE (null) instead.