Aggregate gross rent is calculated by adding together all of the gross rents for occupied housing units in an area. Aggregate gross rent is subject to rounding, which means that all cells in a matrix are rounded to the nearest hundred dollars. (For more information, see "Aggregate" under "Derived Measures".)

The data on meals included in the rent were obtained from answers to long-form questionnaire Item 46b, which was asked on a sample basis at occupied housing units that were rented for cash rent and vacant housing units that were for rent at the time of enumeration. The statistics on meals included in rent are presented for specified renter-occupied and specified vacant-for-rent units. Specified renter-occupied and specified vacant-for-rent units exclude 1-family houses on ten or more acres. (For more information, see "Contract Rent.") This was a new item in 1990 used to measure "congregate" housing, which generally is considered to be housing units where the rent includes meals and other services, such as transportation to shopping and recreation.