CRM document - how to get status duration?

Dear all,

I extract data CRM -> BI using standard datasources: 0CRM_SRV_PROCESS_H, 0CRM_COMPLAINTS_I, etc

I need build a report with status duration of documents

For example, if document was processed 4 days in statuses OPEN > IN PROCESS > VALIDATION > CLOSED report should be following:

OPEN - 1 day

IN PROCESS - 2 days

VALIDATION - 1 day

Each CRM datasource has start date and last change date of the document

But there is no fields which stores date or duration of intermediate status change

Could you please give an advice - how to get status duration?

Thanks in advance