2. Donations and legacies underlying assumptions are based on historical experience and other factors that are considered to be relevant. Actual results may differ from these estimates. The estimates and underlying assumptions are reviewed on an ongoing basis. Revisions to accounting estimates are recognised in the period in which the estimate is revised if the revision affects only that period, or in the period of the revision and future periods if the revision affects the current and future periods. The key estimates that have a significant effect on the amounts recognised in the financial statements are described in the accounting policies and are summarised below: Pension liabilities – The charity recognises its liability to its defined benefit pension scheme which involves a number of estimates as disclosed in note 22. 2021 £’000 2020 £’000 Legacies 140 17 Donations 496 250 Total donations and legacies 636 267 Donations include gifts in kind to the value of £13,040 (2020: £2,978) for professional services provided by 2020 Trustee Services and advertising credits for use on Facebook to the value of £100,788 (2020: £nil) and Google to the value of £82,665 (2020: £nil). The dilapidations – Liability is estimated and disclosed as part of our provisions in note 16. Income – Income is recognised when the entitlement is established, there is probability of receipt and the amount can be reliably measured. Income received relating to future accounting periods is deferred and shown as a creditor on the balance sheet. 81 Financial Statements