Method of accounting.
(13) Method of accounting. For purposes of section 170(b)(1)(A)(vi), an organization's support will be determined under the method of accounting on the basis of which the organization regularly computes its income in keeping its books under section 446. For example, if a grantor makes a grant to an organization payable over a term of years, such grant will be includible in the support fraction of the grantee organization under the method of accounting on the basis of which the grantee organization regularly computes its income in keeping its books under section 446.