Provided, That "service" does not include:
"Behavioral health services" means services provided for the care and treatment of persons with mental illness, mental retardation, developmental disabilities or alcohol or drug abuse problems in an inpatient, residential or outpatient setting, including, but not limited to, habilitative or rehabilitative interventions or services and cooking, cleaning, laundry and personal hygiene services provided for such care: Provided, That gross receipts derived from providing behavioral health services that are included in the provider's measure of tax under article twenty-seven of this chapter shall not be include in that provider's measure of tax under this article. The amendment to this definition in the year 2004 is intended to clarify the intent of the Legislature as to the activities that qualify as behavioral health services, and this clarification shall be applied retrospectively to the effective date of the amendment to this section in which the definition of "behavioral health services" was originally provided as enacted during the first extraordinary session of the Legislature in the year 1993.
W. Va. Code § 11-13A-2