(a) The Kansas standard deduction of an individual, including a husband and wife who are either both residents or who file a joint return as if both were residents, shall be equal to the sum of the standard deduction amount allowed pursuant to this section, and the additional standard deduction amount allowed pursuant to this section for each such deduction allowable to such individual or to such husband and wife under the federal internal revenue code.

(b) For tax year 1998, and all tax years thereafter, the additional standard deduction amount shall be as follows: Single individual and head of household filing status, $850; and married filing status, $700.

(c) (1) For tax year 2013 through tax year 2020, the standard deduction amount of an individual, including husband and wife who are either both residents or who file a joint return as if both were residents, shall be as follows: Single individual filing status, $3,000; married filing status, $7,500; and head of household filing status, $5,500.

(2) For tax year 2021, and all tax years thereafter, the standard deduction amount of an individual, including husband and wife who are either both residents or who file a joint return as if both were residents, shall be as follows: Single individual filing status, $3,500; married filing status, $8,000; and head of household filing status, $6,000.

(d) For purposes of this section, the federal standard deduction allowable to a husband and wife filing separate Kansas income tax returns shall be determined on the basis that separate federal returns were filed, and the federal standard deduction of a husband and wife filing a joint Kansas income tax return shall be determined on the basis that a joint federal income tax return was filed.