An exemption granted under this subparagraph must be revoked for any year in which the owner of the property is no longer a nonprofit housing corporation or the operation of the residential rental housing is an unrelated trade or business to that nonprofit housing corporation.

(a) For the purposes of this subparagraph, the following terms have the following meanings.

(i) "Federally subsidized residential rental housing" means residential rental housing that is subsidized through project-based rental assistance, operating assistance or interest rate subsidies paid or provided by or on behalf of an agency or department of the Federal Government.

(ii) "Nonprofit housing corporation" means a nonprofit corporation organized in the State that is exempt from tax under Section 501(c)(3) of the Code and has among its corporate purposes the provision of services to people of low income or the construction, rehabilitation, ownership or operation of housing.

(iii) "Residential rental housing" means one or more buildings, together with any facilities functionally related and subordinate to the building or buildings, located on one parcel of land and held in common ownership prior to the conversion to nonprofit status and containing 9 or more similarly constructed residential units offered for rental to the general public for use on other than a transient basis, each of which contains separate and complete facilities for living, sleeping, eating, cooking and sanitation.

(iv) "Unrelated trade or business" means any trade or business whose conduct is not substantially related to the exercise or performance by a nonprofit corporation of the purposes or functions constituting the basis