Update in form

[conormooney]

I have a form called 'movements', the fields are AnimalID, Eartagnumber, Entered Herd, Restriction Period, Eligible to leave herd)

I want to type in the date they entered the herd and the restriction period and i want the Eligible to leave herd field to update automatically?

 

[ColinEssex]

Lookup "DateAdd" in Access help.

Col