## Bug description

See [this graph (internal link)](https://app.posthog.com/insights?insight=TRENDS&actions=%5B%7B%22id%22%3A4912%2C%22math%22%3A%22dau%22%2C%22name%22%3A%22Discovered%20Learning%22%2C%22type%22%3A%22actions%22%2C%22order%22%3A0%2C%22properties%22%3A%5B%7B%22key%22%3A%22realm%22%2C%22type%22%3A%22person%22%2C%22value%22%3A%5B%22cloud%22%5D%2C%22operator%22%3A%22exact%22%7D%5D%2C%22math_property%22%3Anull%7D%2C%7B%22id%22%3A7307%2C%22math%22%3A%22total%22%2C%22name%22%3A%22Insights%20Error%20or%20Timeout%20-%20Cloud%22%2C%22type%22%3A%22actions%22%2C%22order%22%3A1%2C%22properties%22%3A%5B%5D%2C%22math_property%22%3Anull%7D%5D&display=ActionsLineGraph&formula=B%2FA&interval=week&date_from=-90d&filter_test_accounts=true&properties=%5B%5D&breakdown=realm&breakdown_type=person#fromItem=190864&fromItemName=%23%20Errors%20Seen%20%2F%20Activated%20User%20-%20Cloud&fromDashboard=3346)

Using formulas + break down doesn't work.

## Expected behavior

Should work.

## How to reproduce

1.
2.
3.

## Environment

- [ ] PostHog Cloud
- [ ] self-hosted PostHog, version/commit: _please provide_

## Additional context



#### *Thank you* for your bug report – we love squashing them!

ee/clickhouse/queries/trends/test/test_formula.py
super().setUp()  
        Person.objects.create(
            team_id=self.team.pk, distinct_ids=["blabla", "anonymous_id"], properties={"$some_prop": "some_val"}
        )
        with freeze_time("2020-01-02T13:01:01Z"):
            _create_event(
                team=self.team,
                event="session start",
                distinct_id="blabla",
                properties={"session duration": 200, "location": "Paris", "$current_url": "http://example.org"},
            )
            _create_event(
                team=self.team,
                event="session start",
                distinct_id="blabla",
                properties={"session duration": 300, "location": "Paris"},
            )
            _create_event(
                team=self.team,
                event="session start",
                distinct_id="blabla",
                properties={"session duration": 400, "location": "London"},
            )
        with freeze_time("2020-01-03T13:01:01Z"):
            _create_event(
                team=self.team,
                event="session start",
                distinct_id="blabla",
                properties={"session duration": 400, "location": "London"},
            )