On February 1, 2020, a company agreed to construct a building at a contract price of $35,000. The company estimated the project would be finished in 2022. Information relating to the costs and billings for this contract is as follows:

2020 2021 2022

Total costs incurred to date $8,000 $10,000 $22,000

Estimated costs to complete 12,000 6,000 -0-

Customer billings to date 8,000 24,000 29,000

Collections to date 4,000 14,000 25,000

The journal entry to record Billings on Construction in Process in 2021 has the amount of _________.