The Maryland disability employment tax credit shall be applicable to all taxable years beginning after December 31, 1996. An employer may claim the credit only for employees hired on or after October 1, 1997. A business entity may not claim the credit for an employee: Who is hired to replace a laid-off employee or to replace an employee who is on strike; or For whom the business entity simultaneously receives federal or State employment training benefits. A business entity may not claim the credit until it has received a certificate in accordance with Regulation .03C of this chapter. A business entity may claim the credit as follows even if an employee's employment lasts less than 1 year: The business entity may claim a tax credit of 20 percent of up to the first $6,000 of wages paid to the employee in the course of employment if the employee voluntarily terminates employment with the employer, if employment began prior to July 1, 2000; If employment began on or after July 1, 2000, the business entity may claim a tax credit of 30 percent of up to the first $6,000 of wages paid to the employee in the course of employment if the employee voluntarily terminates employment with the employer. The business entity may claim a tax credit in proportion to the amount of time worked if the employee works less than a full year because of an inability to continue employment due to a further disability or death, or if the employee is terminated for cause. The same tax credit may not be applied more than once against different taxes by the same taxpayer.