async def runs(self, date: datetime.date = None, days: int = None) -> list:
        """Return all program runs for X days from Y date."""
        endpoint = 'watering/past'

        if date and days:
            endpoint = '{0}/{1}/{2}'.format(
                endpoint, date.strftime('%Y-%m-%d'), days)

        data = await self._request('get', endpoint)
        return data['pastValues']