Thank you for the fast reply

But what is the 1440 in this sum, and i get a answer of 29000 when it should
be 200

"Mally" wrote:

I am designing a spreadsheet for work and want to keep track of how many
items have not been produced due to tool down time.

If i have a target of e.g.100 per hour and the tool is down for e.g. 2hours
(02:00) how can i write this in a formula to show that i have lost 2 hours
which would equal 200 displayed in a column in this example.