changing counts of papers linked to institutions?

[Ivan Sterligov]

Hello everyone,

We are currently researching completeness of the document-to-institution links in OpenAlex vs Scopus on the journal level and were ready to present our findings, but after the Walden release we decided to update the data and instead got quite confused, as the counts are now often  different.  

We rely on API and use the same script for data collection.

The query is constructed using institution id+source id+year as filters, like this:
https://api.openalex.org/works?filter=authorships.institutions.lineage:https://openalex.org/I62916508,publication_year:2020,locations.source.id:https://openalex.org/S2756165422&per_page=1
and returns the count of found papers via json's "meta":{"count"
We mostly focus on big institutions and well-known journals.

As the counts are rather similar and we didn't change the script or API url, it is probably not due to the errors on our side. Any ideas why these counts for the long-gone 2020 are fluctuating? When is it appropriate to collect such data?

Walden release notes do not mention affiliations or institutions but state that "the dataset will continue to evolve and improve, especially this coming month".

We have collected data three times, these are the sample results of fluctuations for TU Munich (https://openalex.org/I62916508) and 2020:

source id June_2025 5-7_November_2025 10_November_2025
https://openalex.org/S105243760 13 14 13
https://openalex.org/S205231332 21 20 20
https://openalex.org/S172538041 2 1 0
https://openalex.org/S19032547 3 4 3
https://openalex.org/S25903957 2 3 2
https://openalex.org/S94610253 3 4 3
https://openalex.org/S118357697 9 8 9
https://openalex.org/S110447773 5 1 5
https://openalex.org/S207313999 2 0 2
https://openalex.org/S177533077 5 2 5
https://openalex.org/S169236886 14 3 14
https://openalex.org/S128124174 2 1 2
https://openalex.org/S149937609 4 3 4
https://openalex.org/S2898225552 2 1 2
https://openalex.org/S32869529 3 2 3
https://openalex.org/S40006715 11 10 11
https://openalex.org/S29980478 7 6 7
https://openalex.org/S191417626 4 5 4
https://openalex.org/S2497375143 4 3 4
https://openalex.org/S173943867 4 2 4
https://openalex.org/S191349260 12 14 12
https://openalex.org/S103321696 14 10 14
https://openalex.org/S94052278 25 18 25
https://openalex.org/S4819472 8 9 8
https://openalex.org/S195255895 14 12 14
https://openalex.org/S164770093 3 1 3
https://openalex.org/S7538555 1 0 1
https://openalex.org/S74970393 10 9 10
https://openalex.org/S3251770 8 7 8
https://openalex.org/S111326731 18 19 18
https://openalex.org/S4502562 12 15 9
https://openalex.org/S201897549 1 0 1
https://openalex.org/S199671312 3 1 3
https://openalex.org/S1393328 1 0 1
https://openalex.org/S2756165422 10 9 10
https://openalex.org/S2876017 4 3 4
https://openalex.org/S58516903 10 9 10
https://openalex.org/S205775358 4 5 4
https://openalex.org/S114430552 6 7 6
https://openalex.org/S148709879 12 11 12
https://openalex.org/S28349394 6 4 6
https://openalex.org/S62201805 2 1 2
https://openalex.org/S152000018 1 0 0
https://openalex.org/S145089992 3 1 3
https://openalex.org/S187585107 43 41 42
https://openalex.org/S175814247 7 6 6
https://openalex.org/S64187185 60 62 62
https://openalex.org/S137905309 1 2 2
https://openalex.org/S127827428 4 3 3
https://openalex.org/S207023548 1 0 0
https://openalex.org/S178776955 3 2 2
https://openalex.org/S173952182 12 13 13
https://openalex.org/S74141806 1 0 0
https://openalex.org/S4210224905 1 0 0
https://openalex.org/S9093621 1 0 0
https://openalex.org/S1980519 9 4 5
https://openalex.org/S90727058 2 1 1

Best regards,

Ivan Sterligov
E-Quadrat Science&Education
Berlin