GA360 User mismatch

For engineers
1

Hi All,

We are encountering an unexpected issue when comparing user counts between GA360 and Snowplow data.
When comparing overall numbers between page_views and structured events we see 2-3% more data is snowplow which is expected, since we do not filter bots etc.

However, when we compare total users between the two, we see a 10% drop in snowplow data, on a monthly basis, (distinct domain_userid)

Screenshot 2024-01-16 at 12.44.16
Screenshot 2024-01-16 at 12.44.161206×750 70.5 KB

Both GA & Snowplow are categorized as ‘Performance’ cookies and require user consent.
We see this drop across browsers, page_path, OS, Geo and cannot see a specific reason causing this.
Our tracker config is pretty basis as well

  newTracker(pageViewsIdentifier, pageViewsEndpoint, {
    appId: "abc",
    platform: "web",
    anonymousTracking: !Cookie.consentGivenFor("performance"),
    eventMethod: "post",
    cookieLifetime: 2 * 365 * 24 * 60 * 60 * 1000,
    contexts: {
      webPage: true,
    },
  });

Any pointers to solving this are highly appreciated