I am trying to build a database that uses a time format of 1234:00 (hhhh:mm)to represent flying hours. I need to proform a calculation that from a given current Flying hours (1500:00 for example) to subtract a previous figure of 1000:00 that will give the result of total hours flown i.e 500 Hours. This has to handle the minutes as well. Any ideas on how I can achieve this?

Martin

start here:
http://www.access-programmers.co.uk/ubb/Forum1/HTML/004785.html

hth,
al