Effective January 1, 1968 the pension payable by any county, municipality or school district to any veteran retired on pension prior to January 1, 1955 pursuant to article 1 of chapter 4 of Title 43 of the Revised Statutes may be increased in accordance with the provisions of this act; provided that the board of chosen freeholders of the county by resolution, or the governing body of the municipality by ordinance, or the board of education of the school district by resolution, as the case may be, shall so determine.
N.J.S. § 43:4-3.1