In general, the number of Customer IDs in DMP is lower than the number of "Visitors" in Analytics.
Number of Customer IDs in DMP:
Number of "Visitors" in Analytics:
The reasons for that are:
- The DMP output (i.e., the table and the number of users) only contains users whose last visit happened within the analysis period. In contrast, the "Visitors" metric in Analytics counts every user who visited the page within the analysis period.
Example: Suppose you create an analysis on Jan 31 and choose the period from Jan 10 to Jan 20 as analysis period. If a user visits the website on Jan 15 (within the analysis period) as well as on Jan 27 (after the analysis period), his Customer ID is not taken into account for this DMP analysis because his last visit did not happen within the analysis period.
- In DMP, there is a automatic data cleanup which follows distinguished rules. This avoids accumulation of data that is not relevant. Therefore, particular Customer IDs are not part of the DMP analysis; nevertheless, each of the corresponding visitors is counted in the "Visitors" metric (as any other visitor). The automatic cleanup rules are described in the Training Chapter DMP – User-centric Data.