<!-- Add the related story/sub-task/bug number, like Resolves#123, or
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**Related issue:** Resolves#48685
# Checklist for submitter
If some of the following don't apply, delete the relevant line.
- [x] Changes file added for user-visible changes in `changes/`,
`orbit/changes/` or `ee/fleetd-chrome/changes`.
See [Changes
files](https://github.com/fleetdm/fleet/blob/main/docs/Contributing/guides/committing-changes.md#changes-files)
for more information.
## Testing
- [x] Added/updated automated tests
- [x] QA'd all new/changed functionality manually
- Tested `ShouldSendStatistics` method manually against our DB, which
covers all our changes.
<!-- This is an auto-generated comment: release notes by coderabbit.ai
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## Summary by CodeRabbit
## Summary by CodeRabbit
* **New Features**
* Added anonymous usage statistics for the number of macOS and Windows
hosts currently enrolled in Fleet’s MDM.
* **Bug Fixes**
* Improved statistics accuracy by counting only actually enrolled,
non-server macOS and Windows hosts that are using Fleet’s MDM.
* **Tests**
* Updated and extended statistics tests to verify the new enrollment
counts are computed and reported correctly.
<!-- end of auto-generated comment: release notes by coderabbit.ai -->