Median year structure built divides the distribution into two equal parts: one-half of the cases falling below the median year structure built and one-half above the median. Median year structure built is computed on the basis of a standard distribution (see the "Standard Distributions" section under "Derived Measures"). Median year structure built is rounded to the nearest whole number. Median age of housing can be obtained by subtracting median year structure built from 2000. For example, if the median year structure built is 1967, the median age of housing in that area is 33 years (2000 minus 1967). (For more information on medians, see "Derived Measures".)