I used itemized deductions of $26,080 on federal return. On Kansas return, the program changed to deduction of $8,772. Why such a large difference?

[KrisD · Accepted solution]

The itemized deduction reported on a Kansas state return K-40 consists of 1/2 real estate tax, 1/2 half of personal property tax, 1/2 mortgage insurance and the charitable donations reported on your Federal return. 

"C1. Real estate taxes from line 6 of federal Schedule A $. Enter 50% of this amount

C2. Personal property taxes from line 7 of federal Schedule A $. Enter 50% of this amount

C3. Qualified residence interest and mortgage insurance premiums you paid and reported on federal Schedule A (see instructions) $. Enter 50% of this amount

C4. Gifts to charity from line 19 of federal Schedule A"

 https://www.ksrevenue.org/forms-ii.html