For purposes of calculating allowable growth under the Nebraska Budget Act, the following shall be treated as an annexation of territory by a regional metropolitan transit authority:

(1) If the municipality that established the transit authority prior to the conversion of such authority into a regional metropolitan transit authority annexes additional territory after such conversion; or

(2) If any other municipality which joined such regional metropolitan transit authority pursuant to subsection (2) of section 18-804 annexes additional territory after joining such regional metropolitan transit authority.