What is the formula that i can use in a cell to calculate the number of remained days till the end of the expiry date that i ve input in another cell

or

the formula that calculate the remained days since the production day already mentioned in a cell

i want to check daily so the calculation should be based on the system date

example : The production date is 01-03-2014 and will expire at 24-4-2014 so i want know how many days left if i check it today(25-03-2014) no problem if a month is 30 or 31 day .

I prefer a formula if available else vba is fine
thank you