Pick the boat type, enter the price new and the age, and the calculator applies the California Board of Equalization's vessel depreciation factors year by year.
Where the factors come from
The Board developed its factors for county assessors to value boats for property tax. It built its database from the BUC Used Boat Price Guide, the N.A.D.A. Marine Appraisal Guide and the ABOS Marine Blue Book, using several years of values from each. Its table:
| Boat type | First year, bought new from a dealer | Each year after |
|---|---|---|
| Powerboat to 42 ft | 12% | 6% |
| Powerboat over 42 ft | 12% | 4% |
| Sailboat | 3% | 3% to year ten, then 1% |
| Personal watercraft | 22% | 8% |
The powerboat factors cover inboard, outboard and sterndrive boats, from bass boats and center consoles to trawlers and yachts. The Board left out houseboats, since most are custom built and the value guides don't list them.
The calculator applies each year's decline to the previous year's value, the way the Board's later letters apply their factors to a prior year's value.
How it compares with the market
The Board later replaced this table with yearly valuation factors, to follow swings in the market. In one of those years the factor for powerboats under 38 ft was 1.05, a rise in value. So treat this table as the shape of a typical decline, and the market as the judge of any one year.
BoatUS describes that shape as an S-curve: a 10% to 15% drop in the first year, around 20% lost by year five for the average dayboat, and 30% to 50% by year ten. Depreciation then speeds up again with age and the boat bottoms out at 10% to 30% of its original value. It names brand, build quality, size, regional demand and the boat's maintenance history, engine hours included, as what slows the decline.
In a valuation
The Board says its table is a guide for mass appraisal and that data on the specific boat should always be considered. A condition and valuation survey works from that data: the boat's condition, its equipment and engine hours, and what comparable boats have sold for. Use the calculator to sanity-check an asking price or a client's expectations, and the copy button to note the figure as a reference.