All experiments
Labs
One machine, many years
Separate the purchase from the expense.
Live experiment
One machine, many years
Carrying amount9,000
Before you move a sliderDoes a longer estimated life change what the machine cost?
Annual depreciation = (12000 − 0) ÷ 4 = 3,000
Read the mechanism
A longer useful life lowers each year's expense, but it does not refund any cash or make the machine worth more. The carrying amount is what is left of the cost to allocate, not a guess at resale value.
Model assumptions and units
Straight-line book depreciation, placed in service at the start of year one. No impairment, additions, tax depreciation or partial years. Depreciation stops at the residual value.