Land can never be depreciated. Since land cannot be depreciated, you need to allocate the original purchase price between land and building. You can use the property tax assessor's values to compute a ratio of the value of the land to the building.

Does land ever lose value?

Land, like any asset, can go down in value, but it doesn't depreciate in the accounting sense. This is important to businesses, because the depreciation of assets is tax-deductible as a business expense.

What is the depreciation rate for land?

Once the building is in use, the assessee business is entitled to claim depreciation on the same at the prescribed rates in force (presently, 10 %).