Section 1913 - Rate of tax(a) If the additional tax was authorized on the basis of amount of tax to be collected, the school board shall, upon the completion of the assessment, fix the rate sufficient to raise the amount determined to be raised at that time with an addition of 10 percent added thereto for delinquencies and costs of collection. If the additional tax was authorized on the basis of a specified rate of taxation, the board shall add thereto 10 percent of said authorized rate for delinquencies and costs of collection. (b) Notwithstanding any other provision of this title to the contrary, any school district which traverses county boundary lines, which has tax rates established in accordance with § 1916(c) of this title, and which subsequently receives approval through referendum to change the limit on such tax rate, shall establish a new or changed tax rate, including the 10 percent for delinquencies and costs of collection, such that the tax rate levied upon the full valuation of real estate will be uniform on all real estate in the school district regardless of the county in which it is located. For purposes of this subsection, the term "tax rate" shall mean the total tax rate levied for all school purposes. For purposes of this subsection, the term "full valuation" shall mean the assessed valuation of a real property divided by the most current assessment to sales price ratio for property within each county among the following sources of such ratios: (1) The aggregate assessment to sales price ratio for all types of real estate in that county as presented in the 1982 Taxable Property Values and Assessments survey for Delaware, United States Bureau of Census. (2) The assessment to sales price ratio established by the Director of the Office of Management and Budget in accordance with § 1707 of this title.(3) The county's assessment to sales ratio used in its most recent assessment.32 Del. Laws, c. 160, § 54; Code 1935, § 2743; 47 Del. Laws, c. 303, § 2; 14 Del. C. 1953, § 1914; 65 Del. Laws, c. 99, §1; 75 Del. Laws, c. 88, § 21(7).;