In 2015, Brennen sold a machine used in his business for $180,000. The machine was purchased eight years ago for $340,000.

In 2015, Brennen sold a machine used in his business for $180,000. The machine was purchased eight years ago for $340,000. Depreciation up to the the date of the sale for regular income tax purposes was $210,000 and $190,000 for AMT purposes.

For AMT purposes, Brennen has a negative adjustment of $ ____________ related to the sale.