N.J. Stat. § 54:4-1.16
If a determination shall be made, either by an assessor or in a judicial proceeding, that a taxpayer is entitled to a reduction in assessment on the grounds that a municipality, on the date of this enactment, was taxing as real property items of machinery, apparatus, and equipment excluded from taxation by this enactment, the municipality shall be entitled to assess that property as personal property and to tax that property in decreasing amounts over a period of five years, at the municipality's general tax rate, in accordance with all laws and procedures established for taxing real property, and in accordance with the following schedule:
First year of reduction: 20% of the total reduction that the taxpayer would otherwise be entitled to;
Second year of reduction: 40% of the total reduction that the taxpayer would otherwise be entitled to;
Third year of reduction: 60% of the total reduction that the taxpayer would otherwise be entitled to;
Fourth year of reduction: 80% of the total reduction that the taxpayer would otherwise be entitled to;
Fifth year of reduction and all years thereafter: 100% of the total reduction;
Provided, however, that the taxpayer may challenge an assessor's determination under this section in a judicial proceeding, and that in such a proceeding the municipality shall bear the burden of proving by a preponderance of the evidence (a) that the item or items had previously been assessed and (b) the assessed value of the item or items.
N.J.S. § 54:4-1.16