At December 31, 2020, the available-for-sale debt portfolio for Cullumber, Inc. is as follows. Security Cost Fair Value Unrealized Gain (Loss) A $17,100 $14,600 $(2,500 ) B 12,500 15,100 2,600 C 22,500 26,000 3,500 Total $52,100 $55,700 3,600 Previous fair value adjustment balance- Dr. Fair value adjustment-Dr. 400 $3,200 On January 20, 2021, Cullumber, Inc. sold security A for $14,700. The sale proceeds are net of brokerage fees. Cullumber, Inc. reports net income in 2020 of $123,000 and in 2021 of $135,000. Total holding gains (including any realized holding gain or loss) equal $40,000 in 2021.