Struggling with a calculation relating to Declining Balance depreciation question.

In recent years, Cullumber Company has purchased three machines. Because of frequent employee turnover in the accounting department, a different accountant was in charge of selecting the depreciation method for each machine, and various methods have been used. Information concerning the machines is summarized in the table below.

Machine		Acquired		Cost		Salvage Value		Useful Life (in years)		Depreciation Method
1		Jan. 1, 2015		$128,500		$18,500		10		Straight-line
2		July 1, 2016		81,500		11,300		5		Declining-balance
3		Nov. 1, 2016		76,800		6,800		7		Units-of-activity

For the declining-balance method, Cullumber Company uses the double-declining rate. For the units-of-activity method, total machine hours are expected to be 35,000. Actual hours of use in the first 3 years were: 2016, 670; 2017, 3,600; and 2018, 4,900.

QUESTION: If Machine 2 was purchased on April 1 instead of July 1, what would be the depreciation expense for this machine in 2016? 2017?

I calculated the following, but I am being told this is incorrect:

Depreciation expense in 2016: $24,300 ($81,000*40%*9/12)

Depreciation expense in 2017: $22,680 ($81,000-$24,300)*40%