Year over Year display

[#1]

Hi, I'm new to Qlik Sense and not too savvy with coding/set analysis.

I would like to first create,basically, the first chart shown in this blog: Year-over-Year Comparisons

However, I'm not sure how to construct it in Qlik Sense. I have months (named PERIOD in my data set and spanning from 2010 to 2015) set as a dimension, but I'm unable to add the PERIOD field as a dimension twice on the line chart. I suspect that the expressions need to be modified.

After creating this line chart, I'd like to compare something like last month's sales with current month sales as a positive or negative KPI indicator, possibly even incorporated as a green or red value within a table I've created. Based on how the user filters the month, I'd like for it to compare current selected months (for example Apr, May, Jun 2014) with the immediate prior months (Jan, Feb, Mar 2014). I'm confident this is possible, I just am unsure of how to accomplish this. I appreciate any thoughts and feedback in advance!

[sinanozdemir]

If you could post a sample data, we can take a look and send you a QVF file.

[#3]

Sure,  a very limited view of the data looks something like this:

PERIOD	BRAND	SALES UNITS	SALES VALUE EUR	PRICE EUR
2013-08	Brand C	0	0	55
2012-09	Brand C	0	0	54
2014-10	Brand C	1	0	0
2014-07	Brand B	0	1	20
2014-08	Brand B	0	1	20
2014-09	Brand B	0	1	20
2015-01	Brand B	0	1	13
2012-11	Brand A	0	1	9
2011-11	Brand C	1	1	1
2012-09	Brand B	1	1	1
2014-01	Brand C	1	1	1
2010-08	Brand B	1	1	1
2011-07	Brand A	1	1	1
2014-01	Brand C	1	1	1
2014-02	Brand A	2	1	1

I'd like to know how to write the expression for a master measure that shows YoY % change in [Sales Value Eur], and the expression for a master measure that shows % change of [Sales Units] and [Price Eur] between the current selected months and the same number of months directly prior to those selected

For example, if the user selects Apr May Jun, the the measure would either sum the sales units or average the price of those months and compare it to Jan Feb Mar's sum sale/average price to ultimately show a positive or negative % growth (incorporating a green and red color code would be awesome). Alternatively, if the user just selects Apr, then it would compare Apr's values with Mar's values.

I know this is a lot to ask, so if anyone can provided resources on learning the syntax, I'd greatly appreciate it.