The tax amount is based on the benefit amount payable. That is, the amount before
any deductions, withholding or offset for medical insurance premiums.
It includes SMI premiums, attorney fees and worker's compensation (see 3.) to the extent they
reduce Social Security benefits payable.
It does not include amounts not paid because of any government pension offset.
The tax amount is computed and rounded to the nearest dime. Amounts ending in 5 are
rounded up (e.g., $37.75 becomes $37.80).