How is the Schedule CA (540) Itemized Deductions Worksheet (line 29) calculated?

My total deduction in line 28 is 30k. I'm single and AGI is over 194,504. Turbotax put 6,000 in line 29 with no explanation. Last year 2017, my AGI is under the limit. I claimed the full 39k. Where does the 6,000 number of this year comes from?