(a) Whenever the most recent federal decennial census shows that any city of the first class has less than seven thousand five hundred (7,500) inhabitants, the city may be reduced to a city of the second class upon the adoption of an ordinance by the council of the municipal corporation requesting that the grade of the municipal corporation be reduced.
(b) The Board of Municipal Corporations, upon the receipt of a certified copy of the resolution, shall make an order reducing the grade of the municipal corporation, and, upon being advised of the action of the board, the Governor shall cause a statement thereof to be prepared and transmitted to the mayor of the city stating the grade to which the municipal corporation has been reduced.