Two issues.
1. Sdawson is correct about CTRL/apostrophe.
2. Otherwise, there IS no previous record. (The Matrix: "There is no spoon...")
This is because in SQL, which is the basis for the JET engine's operation, the word PREVIOUS doesn't truly have a universal meaning. SQL is based on set theory, where the elements are theorized as unordered members of selection sub-domains (hence the term "Domain Aggregate").
On a FORM (or a datasheet, which is an implied form), there is a "PREVIOUS" because the form imposed an order. But the CTRL/apostrophe does what it does DESPITE / OUTSIDE OF set-theory domain concepts.
So there is no SQL function for "previous record's value" because in standard SQL, "previous" and "next" don't exist conceptually.
You can do "PREVIOUS" and "NEXT" via VBA using temporary variables or opening the recordset twice. You can do it on a form because bound controls usually have a "previousvalue" attribute. But you can't do it in SQL.