Attorney's share of recovery

Working with an attorney following a vehicle accident, on a contingency fee agreement. Per contract, attorney is to be paid "from any recovery, settlement or judgement one third of the total amount of said recovery, settlement or judgement after the deduction of any costs."

I understand that "costs" include postage, court costs, etc. Do "costs" also include the amounts I must reimburse Medicare? In other words, does "one third of the total amount of said recovery, settlement or judgement after the deduction of any costs" refer to the 1/3 of total amount recovered minus postage, court costs, etc. or does it refer to postage, court costs, etc plus the amounts I must reimburse Medicare?

To be clear: Assuming a $100,000 recovery "Costs" amount to $1000. Medical reimbursement amounts to $9000.
Does the attorney receive $33,000 (1/3 of $99,000) , or does she receive $30,000 (1/3 of $90,000)?