Table 44 (Median contract rent) located in positions 2888-2896 is incorrect and should not be used. Users who need median rent data can calculate it from the distribution in Table 43. This problem is unique to STF 1B. Table 44 on STP 1A contains the correct data. This median can be calculated by CENSPAC users using the commands shown in the
CENSPAC Report Generation Guide available without charge from Systems and Programming Branch, Data User Services Division, Bureau of the Census, Washington, D.C. 20233. For those users unfamiliar with the algorithm for calculating a median from grouped data, the following is provided:
Computing a Median From Grouped Data
= the lower limit of the class containing the middle, or N/2th item
N = the sum of all frequencies
= the sum of the frequencies in all classes preceding the class containing the N/2th item
= the frequency of the class containing the N/2th
item i = the size of the class interval containing the N/2th item
Example: Computing Median Contract Rent from Table 43-STF 1B
Universe: Specified Renter-Occupied Housing Units Paying Cash Rent
Cash Rent |
Specified Renter Occupied H.U's (fx) |
Cumulative frequency |
Less than $50 |
5 |
5 |
$50 to $99 |
15 |
20 |
$100 to $119 |
28 |
48 |
$120 to $139 |
42 |
90 |
$140 to $159 |
63 |
153 |
$150 to $159 |
59 |
212 |
$160 to $169 |
68 |
280 |
$170 to $199 |
71 |
351 |
$200 to $249 |
55 |
406 |
$250 to $299 |
40 |
446 |
$300 to $399 |
25 |
471 |
$400 to $499 |
18 |
489 |
$500 or more |
0 |
489 |
No cash rent |
2 |
|
Note: The 'No cash rent' class is not used as it falls outside the universe. The N/2th, or middle housing unit falls within the class interval $160 to $169.
Median = $160 + (.478) 10
Median = $164.78, or rounded - $165
Census of Population and Housing, 1980: Summary Tape File 1.