Because of the beginning of the year 2016 opening accumulated depreciation at January 1 2015 value but does not have any impact on the account so there is no need to update in the system.
Since early 2016, the balance of accumulated depreciation value as at January 1, 2015, but without any effect on the account is not required to update the system.
Because the amount of 2016 quoted of accumulated depreciation is worth at 1 January 2015 but no impact any accounting have no need to improve in the system.