VII. Key audit matters are those matters that, in our professional judgment, were of most significance in our audit of the consolidated accounts of the current period. These matters were addressed in the context of our audit of the consolidated accounts as a whole, and in forming our opinion thereon, and we do not provide a separate opinion on these matters. We assessed the provision for pension and other employee benefits presented in the accounts VIII. The EU balance sheet includes pension and other employee benefits amounting to 67,2 billion euro at the end of 2016. This is one of the most significant liabilities in the balance sheet, accounting for almost a third of the total 2016 liabilities of 234,8 billion euro. IX. The majority of this provision for pension and other employee benefits (58,7 billion euro) relates to the Pension Scheme of Officials and Other Servants of the European Union (the ‘PSEO’). This pension liability covers the ‘defined benefit’ guaranteed by Article 83 of the Staff Regulations of Officials of the European Communities (the ‘Staff Regulations’) and Article 4(3) of the Treaty on the European Union (the ‘TEU’). The liability recorded in the accounts reflects the amount which would have been included in a pension fund had one been set up to pay existing retirement pension obligations (5). In addition to retirement pensions, it covers invalidity pensions and pensions paid to widows/orphans of EU officials. Under Article 83 of the Staff Regulations, the benefits paid under the pension scheme are charged to the EU budget, Member States jointly guarantee the payment of the benefits and officials contribute one third of the cost of financing the scheme. X. The PSEO is a mandatory occupational pension scheme for EU civil servants, under which contributions from staff and from the institutions and bodies that employ them are used to finance future pensions. It is designed, through adjustments to the rate of contribution to the scheme and to pensionable age, to be in actuarial balance by default. The number and variety of parameters used to calculate a long-term projection of pension costs underlines the actuarial nature of this calculation, which is ultimately performed by Eurostat on an annual basis. XI. As part of our audit, we evaluated the actuarial assumptions and resulting valuation for the pension provision. We checked the numerical data, the actuarial parameters, the calculation of the provision as well as the presentation in the consolidated balance sheet and the notes to the consolidated financial statements. Our audit of the fair value of the provision detected some incompleteness and inaccuracies in the underlying primary database which do not have a material impact on the EU consolidated accounts. The Commission, as disclosed in note 2.9 to the consolidated financial statements, will take further steps to strengthen its processes used for calculating the employee benefits liability, which we will keep under review. We assessed the accrued charges presented in the accounts XII. At year-end 2016, the Commission estimated that incurred eligible expenses due to the beneficiaries but not yet reported amounted to 102 billion euro (year-end 2015: 106 billion euro). It recorded these as accrued expenses. XIII. We examined the methodologies and control systems for year-end estimates applied in the main directorates-general. We drew samples of invoices and pre-financing payments and carried out work on these elements to address the risk of the accrual having been misstated. We sought additional explanation from the Commission’s accounting services for the general methods applied, and in particular for the new method applied for the 2014-2020 programming period in Cohesion. XIV. The work we performed enables us to conclude that the estimate of the overall amount of accrued charges stated in the consolidated balance sheet is fair for the main directorates-general. However, in some smaller directorates-general we found systemic weaknesses in relation to the year-end entries. The Commission developed an action plan in this respect. We sought additional information from the Commission to support the valuation of financial instruments under shared management XV. Authorities in the Member States transfer a part of the funding advanced by the Commission to financial instruments in the form of loans, equity instruments or guarantees. XVI. For the 2007-2013 multiannual financial framework (MFF), EU law did not require these authorities to produce periodic reports on sums held in these instruments for the preparation of the accounts. The Commission therefore estimated the use made of advances, on the basis of the latest available report (in this case, from year-end 2015), assuming that funds would be used in full and evenly over the period of operation (initially up to 31 December 2015, but later extended to 31 March 2017). We note that even though we find the use of financial instruments in 2016 to be outside the eligibility period (see chapter 6, paragraphs 6.20 and 6.21), the Commission does not seek to recover these amounts. Therefore the presentation in the balance sheet and note 2.5 to the consolidated financial statements reflects this Commission position. XVII. For the 2014-2020 MFF, authorities need to provide information in every cost claim on advances paid to financial instruments and disbursements made from them to final beneficiaries. On the basis of this information an estimated amount is calculated and recognised in the accounts for the period between the date of the last cost claim received and year-end. XVIII. We examined the procedure put in place for recognising the related pre-financing, and we consider that the amount stated in the balance sheet is fair.