When submitting gift aid to HMRC, they will present you with an exact value based on the total of all donations submitted to them. Two donations of £2.50, totalling £5, will produce a total gift aid value of £1.25 at the current tax rate of 20%.
Within Charity CRM, we need to assign this to the two contacts that made the donations. This results in a gift aid of 62.5p per donation and as Charity CRM doesn't make use of decimal pence we have to round this data to 63p. This results in a total gift aid value of £1.26, which is incorrect, and an adjustment needs to be made within Charity CRM.
Once the gift aid claim is moved to a batch, an adjustment will automatically be made within Charity CRM in order to account for difference between the donations and the total. This is typically a negative adjustment, but it can also be positive under the right circumstances if enough round down instead of up.
For this adjustment to happen, a contact within the system needs to be selected. This is calculated via the library definition "GiftAidBalanceContact". The default definition for this library definition is a code snippet which will select the first payment from the claim and assign the adjustment to the contact tied to it. This library definition can be changed with another snippet, or simply a static contact if needed.