Then usable tread depth is compared to remaining tread depth in order to calculate tread wear percentages. For example, a tire that started with 10/32 of original tread depth and has worn off 4/32 (down to 6/32 of remaining tread depth) is 50% worn.
1 If you know the census tract number: Use the IRS list of 2014 Qualified Census Tracts by county. 2  If you have a street address: Visit HUD's interactive QCT Map and enter the property address to view what Census Tract the property is located.
Census tracts generally have a population size between 1,200 and 8,000 people, with an optimum size of 4,000 people. A census tract usually covers a contiguous area; however, the spatial size of census tracts varies widely depending on the density of settlement. Census tract boundaries are delineated with the intention of being maintained over a long time so that statistical comparisons can be made from census to census.