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The detailed guide below is currently available in English.
Straight-line vs. double declining balance
Straight-line divides the depreciable base (cost minus salvage) evenly over the life: a $10,000 asset with $1,000 salvage over 5 years loses $1,800 every year. Double declining balance applies 2 ÷ life to the remaining book value each year, front-loading the expense, and is trimmed so the book value never drops below salvage. Accelerated methods better match assets that lose most value early, like vehicles and electronics.
Book depreciation vs. tax depreciation
The schedule here is for bookkeeping and planning. Tax returns often use different systems with their own tables, conventions, and bonus rules, so the deductible amount can differ substantially from these figures. Use your accounting system or a tax professional for filing numbers.
よくある質問
What is salvage value?
What the asset is expected to be worth when its useful life ends — a resale price, trade-in value, or scrap value. Depreciation stops at this floor.
Which method should I pick?
Straight-line suits assets that wear out evenly. Double declining balance fits anything that loses most of its value in the first years. The total depreciated is the same; only the timing differs.