"Annual payroll" means the total amount of wages for employment paid by an employer during the twelve (12) consecutive calendar month period ending on the computation date of any calendar year, including wages paid by any other employer whose account has been assumed by such employer in accordance with the provisions of IC 22-4-6.5, IC 22-4-10-6, IC 22-4-10-7, or IC 22-4-11.5-7.
IC 22-4-2-16