# Adding a value per visitor (first session trafic source) **URL:** \ **Category:** Data collection and tags\ **Created:** [August 31, 2024, 12:03pm UTC](https://community.piwik.pro/t/adding-a-value-per-visitor-first-session-trafic-source/4366 "2024-08-31T12:03:44Z")\ **Posts on this page:** 3\ **Page:** 1
**Author:** ![LTS22](https://dub1.discourse-cdn.com/flex005/user_avatar/community.piwik.pro/lts22/32/2755_2.png) [@LTS22](https://community.piwik.pro/u/LTS22)\ **Post date:** [August 31, 2024, 12:03pm UTC](https://community.piwik.pro/t/adding-a-value-per-visitor-first-session-trafic-source/4366/1 "2024-08-31T12:03:44Z")
Hello, I was wondering how i could track the first session trafic source of my returning visitors in piwik pro ? Thank you, ---
**Author:** ![Oliwer\_Kaczmarek](https://dub1.discourse-cdn.com/flex005/user_avatar/community.piwik.pro/oliwer_kaczmarek/32/3888_2.png) [@Oliwer\_Kaczmarek](https://community.piwik.pro/u/Oliwer_Kaczmarek)\ **Post date:** [September 4, 2024, 8:31am UTC](https://community.piwik.pro/t/adding-a-value-per-visitor-first-session-trafic-source/4366/2 "2024-09-04T08:31:43Z")
Hi @LTS22, You have this information available in attribution report, but if you want it as a custom session dimension, you’d have to create a cookie or use a local storage to hold this value on your own, then whenever this cookie is recognized in next session (you can check the Piwik PRO [\_pk\_id](https://help.piwik.pro/support/privacy/cookies-created-for-visitors-by-piwik-pro/#_pk_id) cookie which can help you to recognize if it’s the first session or not) you should send custom session dimension. Best, Oliwer ---
**Author:** ![LTS22](https://dub1.discourse-cdn.com/flex005/user_avatar/community.piwik.pro/lts22/32/2755_2.png) [@LTS22](https://community.piwik.pro/u/LTS22)\ **Post date:** [September 6, 2024, 12:16pm UTC](https://community.piwik.pro/t/adding-a-value-per-visitor-first-session-trafic-source/4366/3 "2024-09-06T12:16:28Z")
Makes sense ! Thank you for your reply.