(7)To ensure an efficient use of ESMA's budget and, at the same time, alleviate the financial burden on Member States and the Union, it is necessary to ensure that trade repositories pay at least all the costs related to their supervision. Supervisory fees should be set at a level such as to avoid a significant accumulation of deficit or surplus for activities related to trade repositories. Should deficits occur, ESMA should not recover the deficit from the trade repositories. Should the deficit be significant, ESMA should analyse the reasons and amend its pro-forma supervisory costs for the next budgeting period. With regard to surpluses, surpluses of fees should not be recovered by trade repositories.