# Spreading population growth by period **URL:** \ **Category:** Support - Assistance technique\ **Created:** [3 April 2014 10:42 UTC](https://community.dhis2.org/t/spreading-population-growth-by-period/1960 "2014-04-03T10:42:38Z")\ **Posts on this page:** 4\ **Page:** 1
**Author:** ![Randy\_Wilson](https://dhis2.b-cdn.net/user_avatar/community.dhis2.org/randy_wilson/32/154_2.png) [@Randy\_Wilson](https://community.dhis2.org/u/Randy_Wilson)\ **Post date:** [3 April 2014 10:42 UTC](https://community.dhis2.org/t/spreading-population-growth-by-period/1960/1 "2014-04-03T10:42:38Z")
Hi all, We have a couple of programs that look at their population coverage indicators each month (e.g. ANC 1 coverage rate), yet we only update populations once a year (entering the data or adding projected figures in January). The problem is when you look at coverage monthly you always see a dip in January (see chart below). Is there an established way to spread the population by period? I’ve got the aggregation operator for the Population data element set to “Average” – but presumably that would only have an impact on yearly data if we were analyzing more than 1 year. I can smooth this outside of DHIS-2 by dividing the annual population growth rate by 12 and applying a monthly increase to the January population before calculating coverage. What are the other options? We could enter monthly population projections into the DHIS-2 – but seems like a lot of extra effort and at the facility level they only re-estimate population once a year. ![](https://dhis2.b-cdn.net/uploads/default/original/1X/5b291421c371dda4904b39daa199c925768b57f4.png) **Randy Wilson** ---
**Author:** ![jason](https://dhis2.b-cdn.net/user_avatar/community.dhis2.org/jason/32/32739_2.png) [@jason](https://community.dhis2.org/u/jason)\ **Post date:** [3 April 2014 11:11 UTC](https://community.dhis2.org/t/spreading-population-growth-by-period/1960/2 "2014-04-03T11:11:32Z")
We face exactly the same issue,except it is even more problematic because we are analyzing primarily weekly data. Our solution has been exactly as you have written, to create and import the facility catchment population externally and import. It is a bit of effort but only needs to be done once. A better solution would be preferable though. Regards, Jason ![image](https://dhis2.b-cdn.net/uploads/default/original/1X/5b291421c371dda4904b39daa199c925768b57f4.png) > **···** > > – > > Sent from my mobile > > On Apr 3, 2014 12:43 PM, “Wilson,Randy” [rwilson@msh.org](mailto:rwilson@msh.org) wrote: > > > Hi all, > > > > > > We have a couple of programs that look at their population coverage indicators each month (e.g. ANC 1 coverage rate), yet we only update populations once a year (entering the data or adding projected figures in January). > > > > > > The problem is when you look at coverage monthly you always see a dip in January (see chart below). Is there an established way to spread the population by period? I’ve got the aggregation operator for the Population data element set to “Average” – but presumably that would only have an impact on yearly data if we were analyzing more than 1 year. > > > > > > I can smooth this outside of DHIS-2 by dividing the annual population growth rate by 12 and applying a monthly increase to the January population before calculating coverage. What are the other options? > > > > > > We could enter monthly population projections into the DHIS-2 – but seems like a lot of extra effort and at the facility level they only re-estimate population once a year. > > > > > > > > > > > > ![]() > > > > > > **Randy Wilson** > > > > > > * * * > > > > Mailing list: [https://launchpad.net/~dhis2-users](https://launchpad.net/~dhis2-users) > > > > Post to : [dhis2-users@lists.launchpad.net](mailto:dhis2-users@lists.launchpad.net) > > > > Unsubscribe : [https://launchpad.net/~dhis2-users](https://launchpad.net/~dhis2-users) > > > > More help : [https://help.launchpad.net/ListHelp](https://help.launchpad.net/ListHelp) ---
**Author:** ![Lars](https://dhis2.b-cdn.net/user_avatar/community.dhis2.org/lars/32/34166_2.png) [@Lars](https://community.dhis2.org/u/Lars)\ **Post date:** [3 April 2014 16:11 UTC](https://community.dhis2.org/t/spreading-population-growth-by-period/1960/3 "2014-04-03T16:11:44Z")
dHi, to me it sounds like storing monthly (or quarterly) population data in the system would be the only short/medium-term solution. It will work fine as long as data element aggregation operator is set to average. This to me sounds like an ideal candidate for an [app](http://www.dhis2.org/doc/snapshot/en/user/html/ch29.html) - one that takes i) the org unit level for the yearly population data and ii) the growth rate as input, then applies a linear data addition along the 12 months to make more realistic population data, writes that monthly data back to the system and removes the yearly data after verification. Or less sexy, a bash and curl script against the web api. Lars ![image](https://dhis2.b-cdn.net/uploads/default/original/1X/5b291421c371dda4904b39daa199c925768b57f4.png) > **···** > > On Thu, Apr 3, 2014 at 1:11 PM, Jason Pickering [jason.p.pickering@gmail.com](mailto:jason.p.pickering@gmail.com) wrote: > > > We face exactly the same issue,except it is even more problematic because we are analyzing primarily weekly data. Our solution has been exactly as you have written, to create and import the facility catchment population externally and import. It is a bit of effort but only needs to be done once. A better solution would be preferable though. > > > Regards, > > > > Jason > > > – > > > > Sent from my mobile > > > On Apr 3, 2014 12:43 PM, “Wilson,Randy” [rwilson@msh.org](mailto:rwilson@msh.org) wrote: > > > > Hi all, > > > > > > > > We have a couple of programs that look at their population coverage indicators each month (e.g. ANC 1 coverage rate), yet we only update populations once a year (entering the data or adding projected figures in January). > > > > > > > > The problem is when you look at coverage monthly you always see a dip in January (see chart below). Is there an established way to spread the population by period? I’ve got the aggregation operator for the Population data element set to “Average” – but presumably that would only have an impact on yearly data if we were analyzing more than 1 year. > > > > > > > > I can smooth this outside of DHIS-2 by dividing the annual population growth rate by 12 and applying a monthly increase to the January population before calculating coverage. What are the other options? > > > > > > > > We could enter monthly population projections into the DHIS-2 – but seems like a lot of extra effort and at the facility level they only re-estimate population once a year. > > > > > > > > > > > > > > > > > > > > **Randy Wilson** > > > > > > > > > > > > * * * > > > > > > Mailing list: [https://launchpad.net/~dhis2-users](https://launchpad.net/~dhis2-users) > > > > > > Post to : [dhis2-users@lists.launchpad.net](mailto:dhis2-users@lists.launchpad.net) > > > > > > Unsubscribe : [https://launchpad.net/~dhis2-users](https://launchpad.net/~dhis2-users) > > > > > > More help : [https://help.launchpad.net/ListHelp](https://help.launchpad.net/ListHelp) > > > * * * > > > > Mailing list: [https://launchpad.net/~dhis2-users](https://launchpad.net/~dhis2-users) > > > > Post to : [dhis2-users@lists.launchpad.net](mailto:dhis2-users@lists.launchpad.net) > > > > Unsubscribe : [https://launchpad.net/~dhis2-users](https://launchpad.net/~dhis2-users) > > > > More help : [https://help.launchpad.net/ListHelp](https://help.launchpad.net/ListHelp) ---
**Author:** ![bobj](https://dhis2.b-cdn.net/user_avatar/community.dhis2.org/bobj/32/33033_2.png) [@bobj](https://community.dhis2.org/u/bobj)\ **Post date:** [3 April 2014 16:53 UTC](https://community.dhis2.org/t/spreading-population-growth-by-period/1960/4 "2014-04-03T16:53:26Z")
> dHi, > > to me it sounds like storing monthly (or quarterly) population data in the > system would be the only short/medium-term solution. It will work fine as > long as data element aggregation operator is set to average. > > This to me sounds like an ideal candidate for an app\<[http://www.dhis2.org/doc/snapshot/en/user/html/ch29.html>\-](http://www.dhis2.org/doc/snapshot/en/user/html/ch29.html>%5C-) one that takes i) the org unit level for the yearly population data and > ii) the growth rate as input, then applies a linear data addition along the > 12 months to make more realistic population data, writes that monthly data > back to the system and removes the yearly data after verification. Sounds like a way to do it. I think I'd maybe leave the yearly population rather than delete it and name the calculated dataelements slightly different. The alternative would be to do something smart with the indicator calculation eg. an option to say use the extrapolated (or interpolated for previous years) value from the yearly dataelement when it is being combined in calculation with a monthly. It should be possible to linearly extrapolate on the fly on the basis of previous year's value. Though persisting the monthly values from the calculation is probably simpler and easier on the database. > Or less sexy, a bash and curl script against the web api. Even less sexy bash + psql against the database 🙂 ![image](https://dhis2.b-cdn.net/uploads/default/original/1X/5b291421c371dda4904b39daa199c925768b57f4.png) > **···** > > On 3 April 2014 18:11, Lars Helge Øverland \ wrote: > > > Lars > > > > On Thu, Apr 3, 2014 at 1:11 PM, Jason Pickering \< \> jason.p.pickering@gmail.com\> wrote: > > > > > We face exactly the same issue,except it is even more problematic because > > > we are analyzing primarily weekly data. Our solution has been exactly as > > > you have written, to create and import the facility catchment population > > > externally and import. It is a bit of effort but only needs to be done > > > once. A better solution would be preferable though. > > > > > > Regards, > > > Jason > > > > > > -- > > > Sent from my mobile > > > On Apr 3, 2014 12:43 PM, "Wilson,Randy" \ wrote: > > > > > > >   Hi all, > > > > > > > > We have a couple of programs that look at their population coverage > > > > indicators each month (e.g. ANC 1 coverage rate), yet we only update > > > > populations once a year (entering the data or adding projected figures in > > > > January). > > > > > > > > The problem is when you look at coverage monthly you always see a dip in > > > > January (see chart below). Is there an established way to spread the > > > > population by period? I've got the aggregation operator for the Population > > > > data element set to "Average" - but presumably that would only have an > > > > impact on yearly data if we were analyzing more than 1 year. > > > > > > > > I can smooth this outside of DHIS-2 by dividing the annual population > > > > growth rate by 12 and applying a monthly increase to the January population > > > > before calculating coverage. What are the other options? > > > > > > > > We could enter monthly population projections into the DHIS-2 - but > > > > seems like a lot of extra effort and at the facility level they only > > > > re-estimate population once a year. > > > > > > > > \*Randy Wilson\* > > > > > > > > \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_ > > > > Mailing list: [DHIS 2 Users in Launchpad](https://launchpad.net/~dhis2-users) > > > > Post to : dhis2-users@lists.launchpad.net > > > > Unsubscribe : [DHIS 2 Users in Launchpad](https://launchpad.net/~dhis2-users) > > > > More help : [ListHelp - Launchpad Help](https://help.launchpad.net/ListHelp) > > > > > > \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_ > > > Mailing list: [DHIS 2 Users in Launchpad](https://launchpad.net/~dhis2-users) > > > Post to : dhis2-users@lists.launchpad.net > > > Unsubscribe : [DHIS 2 Users in Launchpad](https://launchpad.net/~dhis2-users) > > > More help : [ListHelp - Launchpad Help](https://help.launchpad.net/ListHelp) > > > > \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_ > > Mailing list: [DHIS 2 Users in Launchpad](https://launchpad.net/~dhis2-users) > > Post to : dhis2-users@lists.launchpad.net > > Unsubscribe : [DHIS 2 Users in Launchpad](https://launchpad.net/~dhis2-users) > > More help : [ListHelp - Launchpad Help](https://help.launchpad.net/ListHelp)