Staff Timesheet in MS Excel

We have a number of staff whose time needs to be recorded including quantity and allocate against both a cost centre (i.e. client) as well as task (i.e. data entry). At the end of each day we need a summary of what time was spent do what task for which client. At the end of the working week (Wednesday to Tuesday), the sheets needs to summarise time by task by client as well as performance e.g. how many records were data entered over what time period and what was the resulted rate - time per unit. I am almost there with the attached but the reporting has me stumped and it is a bit rough. Also the time calculation may be able to be improved upon.