categorical graph in time series dataset

[neptunhiker]

Hi,

I am trying to find a way to create a categorical graph in a time series dataset. Consider the following example of 4 time series:

stockA_1year (500 observations)
stockA_2years (500 observations)
stockB_1year (500 observations)
stockB_2years (500 observations)

So, I have basically 2 stocks for which I have calculated overlapping return data (1 year returns and 2 year returns). Overlapping means that the returns were calculated for example for the 1 year returns: 01/01/2002-01/01/2003, 01/02/2002-01/02/2003, 01/03/2002-01/03/2003, ...)

Now I would like to create a bar graph that shows the mean of the two stocks for 1 and 2year returns respectively. So I would like to have 4 bars in total, but categorized by 1year and 2 year returns. I could do that by plotting a regular bar graph and selecting the series in the following order: stockA_1year, stockB_1year, stockA_2years, stockB_2years. That doesn't give me categories though. Doing that, I will still receive 4 x-axis labels. I would like to reduce those labels to two (i.e. 1year and 2years). The problem is that I don't have an identifier series that could define a category. Is there a way to define categories by common elements inthe names of the series? Or maybe a different way to create a categorical graph without an identifier series?

Thanks a lot for suggestions.