Joy Cunningham Co. purchased a machine on January 1, 2014 for $550,000. At that time, it was estimated that the machine would have a 10-year life and no residual value. On December 31, 2017, the firm's accountant found that the entry for depreciation expense had been omitted in 2015. In addition, management has informed the accountant that the company plans to switch to straight-line depreciation because of a change in the pattern of the way the asset is used, starting with the year 2017. At present, the company uses the sum-of-the-years'-digits method for depreciating equipment.

Instructions:

Prepare the general journal entries that should be made at December 31, 2017 to record these events. Ignore income tax effects.