Need Data from Previous Record to appear in Current Record Field

[catfromtex]

I am a very beginner Access user setting up a form to track gallons of gas pumped from one location to various vehicles. On this form, I am trying to get the data from a previous record’s field (TOTALIZER) to appear in a current record’s field (Proof Gal).


The TOTALIZER number is from a table called Fuel Log_El Rio. The name of the form is also Fuel Log_El Rio.
The code I have written for my control source for the Proof Gal is the following:

=DLookUp("TOTALIZER","Fuel Log_El Rio","[ID]=Forms![Fuel Log_El Rio]![ID]-1")

It is returning a flickering (flashing?) Error message. Could anyone tell me what part of this I have wrong?

Thanks for your help.

[June7]

Do not enclose variables in quote marks. Concatenate variables. Reference to form control is a variable. Is this expression in a textbox on [Fuel Log_El Rio] form?

=DLookUp("TOTALIZER", "Fuel Log_El Rio", "[ID]=" & [ID]-1)

Is the ID an autonumber field? Beware depending on autonumber being sequential, there can be gaps. Here is one query method to get value from another record http://allenbrowne.com/subquery-01.html#AnotherRecord

[catfromtex]

It worked! Thanks so much.