You may need to be able to generate a report of Quantity of Emails by Day, a report for responses per day, or an agent metric reports.
Please follow the Generating Custom Reports in Kayako article to set up the reports and the Building Automation Conditions and Actions for Views, SLAs, and Reports article explains what the conditions mean. For example, you can use "organization" criteria to filter reports based on client's company.
You can also Run Custom Reports on Schedule.
If there is no report matching your requirements, you can retrieve the necessary data using Kayako API calls.