N.M. Admin. Code § 3.1.5.11
Agencies, institutions, instrumentalities and political subdivisions of the state of New Mexico which are subject to the governmental gross receipts tax may treat different taxable activities as different lines of business. Accordingly, one or more activities may be accounted for and reported on a cash basis and one or more other activities may be accounted for and reported on an accrual or modified accrual basis. Once the cash basis, accrual or modified accrual basis has been selected as the method of accounting for and reporting receipts from a particular activity, the activity must continue to be accounted for and reported on the same basis in subsequent periods unless prior permission is received from the department to change the method of accounting or reporting.
N.M. Admin. Code § 3.1.5.11