productivity formula

thanks for the quick reply. productivity as in items completed in the time they have been logged in given that it should only take 7 mins to complete one item. e.g a person is logged in to the system for 1 hr and completes 1 piece of work so 100% of there time is taken on this one piece but it should only take them 7mins to complete so in 1 hour technically they should have completes roughly 8.5 pieces. hopefully this makes sense

i thought it would be average per case / 7 mins * 100 but i keep getting ridiculous figures. appreciate the help thanks