Hi,

I have a long list of timesheets. Each timesheet is on a row and I have about 2,000 of them.

Each timesheet shows:
- start time
- end time
- operator
- machine
- other non-relevant info
with each piece of info in a separate column.

Sometimes only 1 operator will be on a machine, and sometimes 2 or 3 operators will be on the same machine. Sometimes operators 2 and 3 will start after operator 1, and finish before operator 1, or even finish after operator 1.

I am trying to find the sum of all hours that a machine works in the day, irrespective of the number of operators on it.

So if op 1 starts at 6am, and op 2 starts at 7.30am, but then they both work on that machine until 10am, then I want to have 4 hours as the output. If, however, op 2 keeps going on that machine until 10.30am, then the output should be 4.5 hours.

Any ideas of the best way of doing this? I can't work out how to work out how much time is duplicated if another operator clocks on.

Many thanks,

Will