N.M. Admin. Code § 3.5.11.11
The numerator of the property factor shall include the average value of the real and tangible personal property owned or rented by the taxpayer and used in this state during the tax period in the regular course of the trade or business of the taxpayer. Property in transit between locations of the taxpayer to which it belongs shall be considered to be at the destination for purposes of the property factor. Property in transit between a buyer and seller which is included by a taxpayer in the denominator of its property factor in accordance with its regular accounting practices shall be included in the numerator according to the state of destination. The value of mobile or movable property such as construction equipment, trucks or leased electronic equipment which are located within and without this state during the tax period shall be determined for purposes of the numerator of the factor on the basis of total time within the state during the tax period. An automobile assigned to a traveling employee shall be included in the numerator of the factor of the state to which the employee's compensation is assigned under the payroll factor or in the numerator of the state in which the automobile is licensed.
N.M. Admin. Code § 3.5.11.11