# dhis2-devs team mailing list archive

## Re: Average Sum in Org unit Hierarchy

```Hi Lars,
Many thanks, we will eagerly wait for a solution. I have noticed there is a
blue print related to this i.e. although it does not directly fix it but
might be an alternative solution as we wait for this feature.
rgds
David

2016-11-18 14:29 GMT+03:00 Lars Helge Øverland <lars@xxxxxxxxx>:

> Hi Muturi,
>
> yes I see you point. This is something we could look into supporting as a
> setting (include only periods with data in average denominator). I get's a
> bit tricky to implement as we need to weigh the values according to the
> number of days in the data period, and since we need to calculate all this
> with acceptable performance. We will look into it.
>
> Lars
>
>
> On Thu, Nov 17, 2016 at 7:02 PM, David Muturi <dnmuturi@xxxxxxxxx> wrote:
>
>> Hi Lars,
>> Many thanks for your response. Adding a bi-weekly period type will
>> definitely be a good feature to have. However in my example screen shot the
>> value for one month e.g. July is 20 and since it was collected for one week
>> then the average is 20/1 which is 20. What the system is doing is 20
>> /(31/7) = 4.5,given July has 31 days which means the system is including
>> weeks in which no data was collected and mathematically this is incorrect.
>> If formula for calculating this can be fixed to be a count of the weeks in
>> which data is entered (including zeroes) then it would be mathematically
>> correct instead of including periods in which no data is collected.
>> rgds
>> David
>>
>> 2016-11-17 20:49 GMT+03:00 Lars Helge Øverland <lars@xxxxxxxxx>:
>>
>>> Hi David,
>>>
>>> the way the average+sum aggregation works is roughly this:
>>>
>>>
>>> sum( [days in data period] X data value ) / [days-in-aggregation-period]
>>>
>>>
>>> In other words, we take the sum of the product of no of days in the data
>>> value period and data value, divided by no of days in aggregation period.
>>>
>>> Data value period is the period for which the raw data is collected
>>> (weekly in your case). Aggregation period is the period which is requested
>>> in analytics (monthly and quarterly in your case).
>>>
>>> So in this case, the problem is that you capture data by weeks which in
>>> reality represent bi-weeks - this confuses the aggregation output. The
>>> holes in the data (you have many weeks without data) will pull down the
>>> average score. Based on the rules outlined the results seems correct from
>>> what I can see.
>>>
>>>
>>> We could rather look into adding support for a bi-weekly period type.
>>>
>>>
>>> best regards,
>>>
>>> Lars
>>>
>>>
>>>
>>> On Wed, Nov 16, 2016 at 2:24 PM, David Muturi <dnmuturi@xxxxxxxxx>
>>> wrote:
>>>
>>>> Hi Lars,
>>>> Many thanks for your response, since we do not have biweekly defined as
>>>> a dhis2 period type(which would be great to have), we have configured the
>>>> dataset to be weekly but only that data is entered on a biweekly basis,
>>>> meaning one week will miss data while another will have based on when it
>>>> was collected. I have attached an excel download from the datavalues table
>>>> as well as a screen shot showing the weekly periods that data is collected.
>>>> rgds
>>>> David
>>>>
>>>> 2016-11-16 14:08 GMT+03:00 Lars Helge Øverland <lars@xxxxxxxxx>:
>>>>
>>>>> Hi David,
>>>>>
>>>>> sounds strange indeed. We need some more info. Can you include
>>>>> bi-weekly periods in your screenshot so that we can see what the original
>>>>> captured value is?
>>>>>
>>>>> regards,
>>>>>
>>>>> Lars
>>>>>
>>>>>
>>>>>
>>>>> On Mon, Nov 14, 2016 at 8:50 PM, David Muturi <dnmuturi@xxxxxxxxx>
>>>>> wrote:
>>>>>
>>>>>> Hi Team,
>>>>>> I have a data element set us Average sum in org unit hierarchy and
>>>>>> collected on a bi weekly basis, when I select the data in the pivot table,
>>>>>> the average values are bizarre(see attachment). Is this how the above
>>>>>> aggregation operator is meant to work or its a bug?
>>>>>> rgds
>>>>>> David
>>>>>>
>>>>>> _______________________________________________
>>>>>> Post to     : dhis2-devs@xxxxxxxxxxxxxxxxxxx
>>>>>>
>>>>>>
>>>>>
>>>>>
>>>>> --
>>>>> Lars Helge Øverland
>>>>> University of Oslo
>>>>> Skype: larshelgeoverland
>>>>> lars@xxxxxxxxx
>>>>> http://www.dhis2.org <https://www.dhis2.org/>
>>>>>
>>>>>
>>>>
>>>
>>>
>>> --
>>> Lars Helge Øverland
>>> University of Oslo
>>> Skype: larshelgeoverland
>>> lars@xxxxxxxxx
>>> http://www.dhis2.org <https://www.dhis2.org/>
>>>
>>>
>>
>
>
> --
> Lars Helge Øverland