Journal Entries for Over/Under Absorption

Hi,

I have a doubt regarding the journal entries for over and under absorption.
Now Overhead Absorption Rate is based on the Budgeted Level of Activity. That is
OAR = Budgeted Expenditure / Budgeted Activity. Now the OAR is multiplied with the actual Activity to get the Actual Expenditure.
Now considering the T Account i found in the Book for the Production overhead accoutn

Production Overhead Account
____________________________________
Debit | Credit
Labor 6000$ | Work in Progress 27000$
Materials 5000$ | Under absorbed 2000$
Expenses 18000$ |

Total 29000 29000

Now i understand that the Work in Progress is the amount absorbed based on the actual activity. But is the Debit side the expenditure based on the budget activity.?