It is the intent of this section that each register shall receive a fair and adequate compensation for the effort and duties required of the register by the register’s office. The volume and character of work done by the register shall be in comparison to the salary fixed by the Board of Public Works for each of the other registers. Each register is entitled to receive an annual salary of not more than the salary of a State employee at grade 26, step 20 of the State of Maryland Standard and Bargaining Salary Scale in effect on the day before the day that the register begins a new term of office. Any change in the salary paid under the State of Maryland Standard and Bargaining Salary Scale during the term of office of a register may not apply to the incumbent register, but the changed rate shall take effect at the beginning of the next following term of office. The salary of each register shall be determined by the Board of Public Works. In determining the annual salary of the register, the Board of Public Works shall be guided in the exercise of its discretion by: The population of the county determined by the last official United States census; The dollar volume of total fees and taxes collected and excess fees turned over to the State for each of the preceding 5 years by the office of the register for which the salary is being fixed; and Other pertinent data which have relation to the reasonableness of the salary in relation to the work done and volume handled by the office. The salaries of the registers shall be paid semimonthly from the fees and receipts of the office, after deducting the expenses of the office. Expenses include salaries of deputies and clerks, books, stationery, office supplies, and other necessary and customary expenses of doing business. If the fees and receipts of the office are insufficient in any fiscal year to pay all or a part of the expenses of the office and authorized salary of a register, the deficiency shall be funded from the taxes remitted to the Comptroller by the register during that fiscal year. Written authority for the transfer of funds shall be first obtained from the Comptroller. In the event that tax collections for the fiscal year are insufficient, the Comptroller shall make up the deficit from excess fees remitted from all other registers.