Hammer Company is in the process of adjusting and correcting its books at the end of 2017. In reviewing its records, the following information is compiled.

1. Hammer has failed to accrue salaries and wages payable at the end of each of the last 2 years, as follows. The firm paid their employees the $6,100 related to 2016 wages in 2017, but improperly recorded that $6,100 payment as salary expense in 2017. December 31, 2016 $6,100 December 31, 2017 $4,500

2. In reviewing the December 31, 2017, inventory, Hammer discovered errors in its inventory-taking procedures that have caused inventories for the last 3 years to be incorrect, as follows. December 31, 2015 Overstated $ 8,900 December 31, 2016 Understated $15,000 December 31, 2017 Overstated $ 4,600 Hammer has already made an entry that established the incorrect December 31, 2017 inventory amount.

3. At December 31, 2017, Hammer decided to change the depreciation method on its equipment from double-declining-balance to straight-line (starting in 2017). The equipment had an original cost of $400,000 when purchased on January 1, 2016. It has a 5-year useful life and no salvage value. Depreciation expense recorded prior to 2017 under the double-declining-balance method was $160,000. Hammer has already recorded 2017 depreciation expense of $96,000 using the double-declining-balance method.

4. Before 2017, Hammer accounted for its income from long-term construction contracts on the completed-contract basis. Early in 2017, Hammer changed to the percentage-of-completion basis for accounting purposes. It continues to use the completed-contract method for tax purposes. Income for 2017 has been recorded using the percentage-of-completion method. The following information is available.

Prepare the journal entries necessary at December 31, 2017, to record the above corrections and changes. The books are still open for 2017. The income tax rate is 30%. Hammer has not yet recorded its 2017 income tax expense and payable amounts so current-year tax effects may be ignored. Prior-year tax effects must be considered in item 4.