I am having an issue that I am hoping some more experienced DAX programmers may be able to help me with. I have been trying to develop a dashboard in Excel 2013 / PowerPivot / PowerView and one of the graphics I would like to display is a line chart of median performance by hour of day. I would then like to filter the data set with my performance metrics based on a separate column, and link that to a slicer. The medians should be calculated relative to the filtered data set. For the median calculation I am trying to adapt the formula proposed by Marco Russo here (http://sqlblog.com/blogs/marco_russo/archive/2010/07/20/median-calculation-in-dax.aspx).
To illustrate the problem, suppose that I have two tables - main_table and other_table. Main_table has 4 columns- RowID, hour_of_day, performance_metric, and category. Other_table has two columns- hour_of_day and median_column. My goal is to find a formula for median_column such that it shows the median performance metric by hour of day, but can still be sliced by category. The formula I tried to use for the medians was
=CALCULATE(
MINX(
FILTER(
VALUES(main_table[performance_metric]),
CALCULATE(
COUNTA(main_table[performance_metric]),
main_table[performance_metric] <= EARLIER(main_table[performance_metric]))
> COUNTA(main_table[performance_metric]/2),
main_table[performance_metric]),
FILTER(
main_table,
main_table[hour_of_day] = EARLIER(other_table[hour_of_day])))
Or without formatting:
=CALCULATE(MINX(FILTER(VALUES(main_table[performance_metric]), CALCULATE(COUNTA(main_table[performance_metric]), main_table[performance_metric] <= EARLIER(main_table[performance_metric])) > COUNTA(main_table[performance_metric]/2), main_table[performance_metric]), FILTER(main_table, main_table[hour_of_day] = EARLIER(other_table[hour_of_day])))
However, when I create a slicer based on category in main_table, my chart does not seem affected by the slicer. My understanding was that by putting main_table as opposed to ALL(main_table) as the first argument in the last FILTER call, my median calculations would be subject to slices and filters applied to main_table. Am I missing something obvious here?
Calculated columns are apparently computed before queries are executed, therefore anything that needs to be affected by slicers must be entered as a measure, not a calculated column.
Answered in more detail here (http://www.mrexcel.com/forum/powerpivot-questions/741071-medians-context-issues-dax.html#post3641780)
Related
In PowerBI, I need to create a Performance Indicator (KPI) measure which evaluates dataset values in a scale from 0 to 1, with target (1) being the MAX value in a 20 years history. It's a national airport trip records open database. The formula is basically [value]/[max value].
My dataset has a lot of fields and I wish I could filter it by any of these fields, with a line chart showing the 0-1 indicator for each month based on the filters.
This is my workaround test solution:
Table 1 - Original dataset: if I filter something here, below tables also update (there are more fields to the left, including YEAR and MONTH
Table 2 - Reference to original dataset, aggregating YEAR-MONTH by the sum of "take-offs" (decolagens)
Table 3 - Reference to above (sum) table, aggregating MONTH by the max of "take-offs" (decolagens)
Table 4 - 'Sum table' merged to 'Max table' by MONTH as new table: then do [Value]/[Max] and we've got the indicator
So if i filter the original dataset by any fields, all other tables update accordingly and the indicators always stays between 0-1, works like a charm.
TL;DR
The problem is: I need to create a dashboard of this on Power Bi. So I need this calculation to be in a measure or another workaround.
My possible solution: by pure DAX code in the measure field, to produce Tables 2 and 3 so I'll divide the month sum values by their month max value (which will both be produced according to PowerBi dashboard slicers) and get the indicator dinamically produced.
I'm stuck at: I don't understand how can I reference a sum/max aggregate table in dax code. Something like = SUM (dataset[take-offs]) / MAX (SUM (dataset[take-offs])). Of course these functions do not work like that, but I hope I made my point clear: how can I produce this four table effect with a single measure?
Other solutions are welcome.
Link to the original dataset: https://www.anac.gov.br/assuntos/dados-e-estatisticas/dados-estatisticos/arquivos/DadosEstatsticos.csv
It's an open dataset, so I guess there's no problem sharing it. Please help! :)
EDIT: please download the dataset and try to solve this. Personally I think it's a quality statistics doubt that will eventually help others. The calculation works, it only needs a Power Bi Measure port.
Add the ALL formula:
Measure = SUMX(ALL('Table'),[Valor])/SUM('Table'[Max])
Example
I'm looking a way to add an extra column in a pivot table that that averages the sum of the count for the months ("Count of records" column) within a time period that is selected (currently 2016 - one month, 2017 - full year, 2018 - 5 month). Every month would have the same number based on the year average, needs to be dynamically changing when selecting different period: full year or for example 4 months. I need the column within the pivot table, so it could be used for a future pivot chart.
I can't simply use average as all my records appear only once and I use Count to aggregate those numbers ("Count of records" column).
My current data looks like this:
The final result should look like this:
I assume that it somehow can be done with the help of "calculated filed" option but I couldn't make it work now.
Greatly appreciate any help!
Using the DataModel (built in to Excel 2013 and later) you can write really cool formulas inside PivotTables called Measures that can do this kind of thing. Take the example below:
As you can see, the Cust Count & Average field gives a count of transactions by month but also gives the average of those monthly readings for the subtotal lines (i.e. the 2017 Total and 2018 Total lines) using the below DAX formula:
=AVERAGEX(SUMMARIZE(Table1,[Customer (Month)],"x",COUNTA(Table1[Customer])),[x])
That just says "Summarize this table by count of the customer field by month, call the resulting summarization field 'x', and then give me the average of that field x".
Because DAX measures are executed within the context of the PivotTable, you get the count that you want for months, and you get the average that you want for the yearly subtotals.
Hard to explain, but demonstrates that DAX can certainly do this for you.
See my answer at the following link for an example of how to add data to the DataModel and how to subsequently write measures:
Using the Excel SMALL function with filtering criteria AND ignoring zeros
I also recommend grabbing yourself a book called Supercharge Excel when you learn to write DAX by Matt Allington, and perhaps even taking his awesome online course, because it covers this kind of thing very well, and will save you significant head-scratching compared to going it alone.
Is there a way to let a pivot table calculate the difference between 2 columns automatically when the values are shown as a % of the parent column total?
Now I need to to manually but the table is dynamic and number of competitors may vary. Function seems so easy but can't find it after googling etc...
See example picture below of what I want to achieve.
(Column F automated by the pivot table is the goal)
If trying to solve this with PivotTables, you've got a couple of options:
Use a 'Traditional' PivotTable that's based on a range. This will give you percentage differences, but you can't get percentage point differences like you're asking for without using external formulas.
Use a 'OLAP' PivotTable that's based on data you've added to the Excel Data Model. This will give you both percentage differences and percentage point differences, without having to resort to using external formulas.
In both cases, I recommend that you unpivot your data first, so that it is in what's known as a Flat File. Currently you're using a cross-tabulated data source (i.e. your source has columns called Year 1, Year 2), and the type of percentage comparisons across years you want to do doesn't work if your data is a crosstab. Basically, PivotTables aren't meant to consume cross-tabulated data.
Instead, you really want your data laid out so that you have a column called Amount and a column called Year, and then you can use the Show Values As options available from the right-click menu to show as percentage differences across years. To transform your data into a flat file, see my answers at convert cross table to list to make pivot table
That said, you can still use the GETPIVOTDATA function on your existing (unpivoted) data layout in a way that is somewhat more robust to changes in your PivotTable structure than just subtracting one reference from the other:
But again, I recommend transforming your data into a Flat File. Then you can additionally do the following:
Using a 'Traditional' PivotTable:
You can kinda solve your problem entirely within a self contained 'Traditional' PivotTable if you drag the Amount column to the Values area, put the Year column in the Columns area, put your Competitors in the Rows area, and choose one of the percentage Show Values As options you'll see when you right-click a cell in the Values area.
I say kinda, because without using external formulas (or without calculating the percentages back in your source data), you can only get it to show percent increases (see far right column), not percentage point increase like you want (see far left column). That said, I think percent increase is less confusing. But I guess it depends on what you want to show. If you want to show say change in market share from one year to the next, then percentage points make sense.
Of course, you could always use the GETPIVOTDATA function to do the additional math for you like we did earlier, like I've done on that left hand side.
Using an OLAP PivotTable based on the DataModel
Calculating percentage point increases likely requires using PivotTables built using the Data Model. See my answer at https://stackoverflow.com/a/49973465/2507160 that explains a little about the Data Model (although it doesn't answer this specific question).
Here's the result:
Here's the measures I used to do this:
Total Year 1:
=CALCULATE(SUM(Table2[Value]),ALLSELECTED(Table2[Competitor]),Table2[Year] = "Year 1")
Total Year 2:
=CALCULATE(SUM(Table2[Value]),ALLSELECTED(Table2[Competitor]),Table2[Year] = "Year 2")
% Year 1:
=CALCULATE(SUM(Table2[Value]),Table2[Year] = "Year 1")/[Total Year 1]
% Year 2:
=CALCULATE(SUM(Table2[Value]),Table2[Year] = "Year 2")/[Total Year 2]
p.p. Diff:
= [% Year 2] -[% Year 1]
You can add Calculated Fields to Pivot Tables, of varying levels of complexity. Finding the difference between two fields is about as simple as it gets.
The example below is borrowed from contextures.com, where there are many more examples more further information.
To add a calculated field:
Select a cell in the pivot table, and on the Excel Ribbon, under the PivotTable Tools tab, click the Options tab (Analyze tab in
Excel 2013).
In the Calculations group, click Fields, Items, & Sets, and then click Calculated Field.
Type a name for the calculated field, for example, RepBonus.
In the Formula box, type =Total * 3%
Click Add to save the calculated field, and click Close.
The RepBonus field appears in the Values area of the pivot table, and in the field list in the PivotTable Field List.
(Source)
EDIT:
#jeffreyweir - I'm not gonna lie, I don't know off the top of my head how to make this work (and don't have time to experiment) but by the looks of these options, isn't a calculated field with a "straight subtraction" of existing fields (ie., 3$-2%=1%) very possible with Difference from? (as opposed to % Difference from which is also an option but for a different result).
In fact, automatic year-over-year difference reporting should be readily possible with the <previous> and <next> comparison operators...?
(Click to Embiggen)
Also, did you see the link where I got the example? Kind of a hoakey site but it has some more complex pivot table instructions.
I'm trying to get the average number of "on time shipment" based on items rolled up to "ship numbers" and then by "order number". I have one order number in this scenario that is shipped via multiple shipments. It seems to me that after rolling it up via PowerPivot and then creating a pivot table, it's calculating the average based on the total lines of the "order number" instead the pivot.
PowerPivot Data:
Pivot based on data above:
How can I get the average number based on the pivot table rather than the PowerPivot total data of the order number? I'm probably not making any sense, but hopefully the images below explain it better. As you can see, when you roll up the items by ship number then by order number, you'll see that the actual average is 0.6 but the pivot is showing 0.5.
Help!
Technically speaking, the average is correct - if you look at the source data, for some reason all rows are duplicated and if you do regular average calculation, it's actually 0.5.
What you are looking for is calculating average for distinct values, which can be done easily with AVERAGEX function.
I have copied your table and created those 2 Calculated Fields (in Excel 2010, it's Measures):
Average on Time:
=AVERAGE(Table1[On Time])
Average on Time (UNIQUE)
=AVERAGEX(VALUES(Table1[Ship Number]), [Average on Time])
Using AverageX with VALUES() function makes it easier to calculate any expression ONLY for unique values.
If you then put both measures on PivotTable, you should get this:
First column is same as yours (using "regular" AVERAGE function). The second one shows the average calculated over distinct (unique) values of Ship Numbers.
Hope this helps.
PS: This great article by Kasper de Jonge helped me quite a bit with similar scenarios.
I have created a power pivot table as shown in the picture. I want to calculate quarter over quarter sales change. For which I have to divide for example corporate family "Acer" 's sales in 2012Q4 by sum of all the corporate family. I am using calculated measure to do this, but I am not sure what formula I can use.
My need is to create two columns, one for 2012Q4 percent of total and one for 2013Q1 percent of total. Then I will create another measure to find the difference. So the formula for 2012Q4 should be like this 1624442 / (1624442+22449+1200+16123) . Any idea which function can help me do it?
It sounds like you are measuring the change in the percent of total for each corporate family from quarter to quarter. You will need to create 3 calculated measures. I'm not sure what your model looks like so I can't give you the exact formula, but here is the idea.
CurrentQtr%ofTotal:= Divide(Sum('Sales'[Units]),Calculate(Sum('Sales'[Units]), All['Product'[Corporate Family])))
PrevQtr%ofTotal:= DIVIDE(CALCULATE(Sum('Sales'[Units]), DATEADD(DimDate[DateKey], -1, QUARTER)),
CALCULATE(Sum('Sales'[Units]), DATEADD(DimDate[DateKey], -1, QUARTER), All('Product'[Corporate Family]))))
Change%ofTotal:= DIVIDE(([CurrentQtr%ofTotal]-[PrevQtr%ofTotal]),[PrevQtr%ofTotal])
I used the divide function because it handles divide by zero errors. You use the ALL function to remove the filter on the Corporate Family column from the filter context. The Change%ofTotal is just to find the differenc. I'm calculating % change but you may just want to subtract.
Here's the link to a good blog post on time intelligence. And here's one on calculating percent of total.
For percentages please follow the tutorial on the Tech on the Net.
Adding another column where you calculate a difference between two pivot columns will not work - this column is "unpivotable", as it relies on a column defintion. You would need to copy and paste pivot as values to another worksheet and do the extra calculation there.