On january 1, year 7, colorado corp. purchased a machine having an estimated useful life of 8 years and no salvage value. the machine was depreciated by the double-declining-balance (ddb) method for both financial statement and income tax reporting. on january 1, year 9, colorado justifiably changed to the straight-line method for both financial statement and income tax reporting. accumulated depreciation at december 31, year 8, was $525,000. if the straight-line method had been used, the accumulated depreciation at december 31, year 8, would have been $300,000. the retroactive adjustment to the accumulated depreciation account on january 1, year 9, as a result of the change in depreciation method is a. $225,000
b. $525,000
c. $300,000
d. $0