How to set a field cumulating multiple days integer field data collection either in Formbuilder or in XLSFORM?

We are health project in Guinea, implementing COCID-19 Preparation and Response Project in Guinea Conakry (West Africa). The 2nd vaccination campaign is forseeing 2 millions of Johnson and Johnson vaccines to vaccinate 60% of population (two age ranges 12 to 17 years old and equal or greanter than 18 years old. As IT in Project Implementing Unit (PIU), I’m in charge of developping vaccination data collection form in kobotoolbox on Researchers platform ( to collect statistics on number of people vaccinated and vaccinator by gender (male and female), number of adverse event postvaccinated people, vaccination equipment such are cold room, refrigerant truck, Off gel cooler, Isothermal box 80°C, Generator, Incinerator, Glass grinder, trash bag, vaccination card, tablet in each health facilitity.
Our health system has a National Agency for Health Security (ANSS) which will deploy its staff as vaccinators, data collectors around the country during 3 months to vaccinate population. They spent already 3 weeks to vaccinate people.
When I presentated the form beside the IT, enumerators staff of ANSS, they required me to set on the form a field cumulating multiple days integer field data collection as shown on screenshot in attached document (Cumulated number of people vaccinated, Cumulated serious or minor AEPV). But Has any XLSFORM or Formbuilder function that can help setting this cumulated number field on form since the form is not permanently connected to the backend kobo database, it is blank for new collection but cannot report in a field the numbers of vaccinated people cumulated for previous to present day and add to present day number…Please need your help if this function exists.


  1. Write xlsform code in Excel for the form with cumulated number field set in form
  2. Check code from XLSFORM Online v2.x
  3. Load form for end user enumerator
  4. Input number of people vaccinated in Day 1 field (as shown on screenshot)
  5. Input number of people vaccinated in Day 2 field
  6. Get Cumulated number of people vaccinated filled automatically filled with Day 1 number + Day 2 number

Not sure that function exists in Kobo or need help from kobo developpers

D. ADDITIONAL DETAILS (Attachments with screenchots)

Have you checked out the custom report? Maybe the results there should solve your issue?

Dear Kal_Lam,
Of course back end host the database in kobo that you can export in excel, or go through report (by customizing or direct displaying) to see cumulated number of vaccinated people and serious or minor AEPV. The National Agency for Health Security (ANSS) IT and enumerators need the cumulated number field to be set on the blank form every collection beginning day since the blank form is not synchronized every time with kobo back end database (whatever format : Exportable Excel file, Report, Data overview grid, GPS)

Maybe if this is the case, you will need to try out the case management as outlined in the support article: