The original cost of a machine was $1,000,000. Its original salvage value was $100,000 and it had an original useful life of 9 years. In year 4 of the machine's life, the company decided the total useful life of the machine should be 12 years. The salvage value was kept at $100,000. What would the year 4 depreciation expense be?

a) $50,000

b) $100,000

c) $66,667

d) $55,556