Calculate quantity built based on 2 x 12 hour shift pattern

Hi,

I have a table that provides me with a quantity build and the date/time that item was built. We are moving to a 2 x 12 hour shift pattern runny 7am to 7pm and then 7pm to 7am.

I want to break down the quantity built into these shifts so we can see productiuvity. How would I go about doing so?

Thanks

Craig