For assets acquired during the year (i.e. not on January 1), the sum-of-the-years digits method requires that the same depreciation rate be used:

		for the remaining months of the year of acquisition, then again in the final year of the assets estimated life for any months not depreciated in year 1
		for 12 consecutive months, even if that results in the same rate being used in two different calendar years
		throughout the life of the asset
		until the end of the calendar year, then recomputed for the next calendar year
		any of the above methods is acceptable, as long as the company uses the same method for every asset that it owns