(2) Either:

(a) Was subject to an allowance for depreciation under the Code on April 1st of the property tax year to which the claim for reimbursement relates or would have been subject to an allowance for depreciation under the Code as of that date but for the fact that the property has been fully depreciated; or

(b) In the case of construction in progress or inventory parts, would be subject under the Code to an allowance for depreciation when placed in service or would have been subject to an allowance for depreciation under the Code as of that date but for the fact that the property has been fully depreciated.

"Business property" also includes all property that is affixed or attached to a building or other real estate if it is used to further a particular trade or business activity taking place in that building or on that real estate. "Business property" does not include components or attachments to a building if used primarily to serve the building as a building, regardless of the particular trade or activity taking place in or on the building. "Business property" also does not include land improvements if used primarily to further the use of the land as land, regardless of the particular trade or business activities taking place in or on the land. In the case of construction in progress or inventory parts, the term "used" means intended to be used. "Business property" also does not include any vehicle registered for on-road use on which a tax assessed pursuant to chapter 111 has been paid or any watercraft registered for use on state waters on which a tax assessed pursuant to chapter 112 has been paid.

B.__"Inventory parts" includes repair parts, replacement parts, replacement equipment, additions, accessions and accessories on hand but not in service and stocks or inventories of repair parts, replacement parts, replacement equipment, additions, accessions and accessories on hand but not in service if acquired after April 1, 2005, regardless of when placed in service.

2.__Phaseout of tax on business property.__An exemption from the personal property tax levied pursuant to this Part is