56Accordingly the answer to the first question is that clause 5(1)(a) of the FTW Framework Agreement must be interpreted as meaning that a temporary need for replacement staff, provided for by national legislation such as that at issue in the main proceedings, may, in principle, constitute an objective reason under that clause. The mere fact that an employer may have to employ temporary replacements on a recurring, or even permanent, basis and that those replacements may also be covered by the hiring of employees under employment contracts of indefinite duration does not mean that there is no objective reason under clause 5(1)(a) of the FTW Framework Agreement or that there is abuse within the meaning of that clause. However, in the assessment of the issue whether the renewal of fixed-term employment contracts or relationships is justified by such an objective reason, the authorities of the Member States must, for matters falling within their sphere of competence, take account of all the circumstances of the case, including the number and cumulative duration of the fixed-term employment contracts or relationships concluded in the past with the same employer.