# 537.4 Definitions.
(a) *Statutory terms.* (1) The terms *average fuel economy standard, fuel, manufacture,* and *model year* are used as defined in 49 U.S.C. 32901.
(2) The term *manufacturer* is used as defined in 49 U.S.C. 32901 and in accordance with part 529 of this chapter.
(3) The terms *average fuel economy, fuel economy,* and *model type* are used as defined in subpart A of 40 CFR part 600.
(4) The terms *automobile, automobile capable of off-highway operation,* and *passenger automobile* are used as defined in 49 U.S.C. 32901 and in accordance with the determinations in part 523 of this chapter.
(b) *Other terms.* (1) The term *loaded vehicle weight* is used as defined in subpart A of 40 CFR part 86.
(2) The terms *axle ratio, base level, body style, car line, combined fuel economy, engine code, equivalent test weight, gross vehicle weight, inertia weight, transmission class,* and *vehicle configuration* are used as defined in subpart A of 40 CFR part 600.
(3) The term *light truck* is used as defined in part 523 of this chapter and in accordance with determinations in that part.
(4) The terms *approach angle, axle clearance, brakeover angle, cargo carrying volume, departure angle, passenger carrying volume, running clearance,* and *temporary living quarters* are used as defined in part 523 of this chapter.
(5) The term *incomplete automobile manufacturer* is used as defined in part 529 of this chapter.
(6) As used in this part, unless otherwise required by the context:
(i) *Administrator* means the Administrator of the National Highway Traffic Safety Administration or the Administrator's delegate.
(ii) *Current model year* means:
(A) In the case of a pre-model year report, the full model year immediately following the period during which that report is required by § 537.5(b) to be submitted.
(B) In the case of a mid-model year report, the model year during which that report is required by § 537.5(b) to be submitted.
(iii) *Average* means a production-weighted harmonic average.
(iv) *Total drive ratio* means the ratio of an automobile's engine rotational speed (in revolutions per minute) to the automobile's forward speed (in miles per hour).
[89 FR 52953, June 24, 2024]