Charting problem exchange rates

[chefe]

Hi there,

I am struggling with a specific chart, display exchange rates.

I downloaded some exchange rate data and formulated a measure to give me the relative development of each rate.

E.g. = (rate today) / (rate in index year) ... so I can compare the releative performance of different exchange rates.

The pbix file is here to look at: http://1drv.ms/20S3yCM

The page filter is set to display to exchange rates, USD and CHF (each against EUR). In the first chart my measure somehow aggregates the two currencies and displays the releative changes, for each day.

In the second chart I dragged the "currencies" data field onto the chart legend to have two series. But what happens now I do not understand. Two series are shown BUT the scale there seems to be some sort of aggregation going on, meaning the increments are different than before. You also see that the series lines seem different from the appearance...it seems the data is not shown for each day as before.

Does somebody know what I am doing wrong?

Best regards

[SqlJason]

Looks like it is because the second line chart is not displaying all the values (you should see a yellow warning symbol on the top left). To prove this, you can try filtering the report to an earlier date, let's say Feb 1, and then the scale should be the same for both the charts,

[chefe]

Hi there, thank you for your reply!

I'll play around with that idea, but I am certain the underlying data (apart from the exchange rates themselves) is identical, so for each date the is a rate. Even if I throw away the second chart, change the page filter to only "USD", and afterwards put the currency data field in the legend, the same happens...

I would have expected the series line to remain the same and only for a legend to show up showing the currency name. But no luck. Any thoughts?

Maybe: Is my data table "structured" incorrectly?

[SqlJason]

I don't think changing the model is going to help you with the error message (I just tried creating a proper dimensional model with a star schema structure with Currency and Date dimensions, and still got the same error).

I think it has got to do with the fact that Power BI can only take around 1000 points (I think that is the limit) currently, and even if you are putting a filtered attribute (like currency), it would still calculate the number of points based on what the unfiltered list looks like. For eg, in your case, there are 31 values for curency and around 35 dates in the line chart (ideally you should have much more dates, but only 35 are appearing).

Hopefully this will change in the future, as was told by Will T from Microsoft Power BI team.

http://community.powerbi.com/t5/Desktop/Too-many-values/td-p/2939/page/2