I have this table where the following fields are listed:
Basically each Fare Basis value has a specific time lenght (e.g. 24/10/2017 - 06/12/2017) and it features a different CXR (e.g. QF, SQ), a variable class (e.g. Y,J,F) a specific level, tfc. and AIF. Such periods do overlap but they will be charachterized by different CXR and therefore level, tfc and aif.
What i need to do is creating a measure that indidicates the AIF difference between QF and others CXR for specific periods (that therefore can be selected in a time range) and class.
This sounds like a job for the EARLIER() Function. This function allows you to create calculated columns that can compare/summarize values using values from other rows. Honestly, it's hard to explain EARLIER() but it works, so the best way to learn is by example and just watching the magic happen. For your scenario, if you wanted to sum all of Qantas' AIF, you could do that with the following syntax/steps:
Total AIF = CALCULATE(SUM([AIF]),FILTER('TABLE NAME','TABLE NAME'[CXR]=EARLIER('TABLE NAME'[CXR])))
*Please note you would need to replace 'TABLE NAME' with the name of your table where this data is stored. Also, Total AIF is the name of the calculated column.
This measure will sum the AIF for each carrier, regardless of time frame. SO if you wanted to compare the difference between Carriers, you could make a carrier specific formula to add up the AIF like so:
From here, you could create a formula for each carrier if you wanted to compare the differences between each. You should also be able to slice these formulas by the [date] column in your data visualizations.