1.  Except as otherwise expressly provided in a particular statute or required by the context, ‘population’ means the number of people in a specified area as determined by the last preceding national decennial census conducted by the Bureau of the Census of the United States Department of Commerce pursuant to Section 2 of Article I of the Constitution of the United States and reported by the Secretary of Commerce to the Governor pursuant to 13 U.S.C. § 141(c). The tabulations of population reported by the Secretary of Commerce for a particular decennial census date shall be deemed to apply for the purposes of this section from July 1 of the calendar year immediately following that decennial census date until June 30 of the calendar year immediately following the next decennial census date.

2.  As used in this section, ‘decennial census date’ means the first day of April of 1980 and every 10 years thereafter on which the decennial census is taken pursuant to federal law.