OMB -2528-0029 -SS Manufactured Homes Part B

Supporting Statement for Paperwork Reduction Act Submissions

Manufactured Housing Survey

(OMB# 2528-0029)

Form C-MH-9A

B. Collections of Information Employing Statistical Methods

1. Describe (including a numerical estimate) the potential respondent universe and any sampling or other respondent selection methods to be used. Data on the number of entities (e.g., establishments, State and local government units, households, or persons) in the universe covered by the collection and in the corresponding sample are to be provided in tabular form for the universe as a whole and for each of the strata in the proposed sample. Indicate expected response rates for the collection as a whole. If the collection had been conducted previously, include the actual response rate achieved during the last collection.

A file of all manufactured homes sections shipped during the month is provided to the Census Bureau by the Institute for Building Technology and Safety (IBTS). IBTS provides the file to Census on a monthly basis under the terms of a contractual agreement. The file identifies each home section by serial number and shows the name, street, city, and state of the dealership that received the home. This file serves as the universe for the survey. Any home sections identified as FEMA shipments are removed from the frame prior to sampling and added to the sample with certainty. Of the roughly 7,700 homes shipped each month, a fixed sample of 405 homes is randomly selected for the survey. A systematic sample of fixed size is taken from each of the four Census regions. The current response rate is approximately 72 percent. The total quantity response rate for price is about 63 percent.

2. Describe the procedures for the collection of information including:

• Statistical methodology for stratification and sample selection,

• Estimation procedure,

• Degree of accuracy needed for the purpose described in the justification,

• Unusual problems requiring specialized sampling procedures, and

• Any use of periodic (less frequent than annual) data collection cycles to reduce burden.

The form C-MH-9A imprinted with a letter signed by the Director of the Census Bureau, (see Attachment 2) explaining the survey and identifying the home, is mailed to the manufactured home dealer shown as the receiver of the sampled home. The letter is sent four months after the shipment month. Dealers can respond by internet, mail, fax, or telephone. Calls are made to dealers who fail to respond.

Each sampled home is weighted by its inverse probability of selection divided by the number of sections in the home. Respondent data is reviewed for consistency across related items. Imputations are made for missing data due to unit or item nonresponse. Estimates of manufactured housing shipments by status are calculated using the sample weight and an adjustment to the population control totals of homes shipped by single or multi section. Estimates of average sales prices by region include both actual sales prices and intended sales prices (if home is not yet sold at time of data collection).

The average relative standard error of monthly estimates of national level shipments placed/sold for residential use (based on the 2017 monthly data) is about 5.6 percent. The average relative standard error of monthly estimates of national level shipments intended for sale for residential use (based on the 2017 monthly data) is about 8.6 percent. The average relative standard error of monthly estimates of average sales price (based on 2017 monthly data) is about 2.5 percent for the U.S. and approximately 4.6 percent at the regional level.

3. Describe methods to maximize response rates and to deal with issues of non-response. The accuracy and reliability of information collected must be shown to be adequate for intended uses. For collections based on sampling, a special justification must be provided for any collection that will not yield "reliable" data that can be generalized to the universe studied.

Telephone follow-ups are used to reduce nonresponse.

4. Describe any tests of procedures or methods to be undertaken. Testing is encouraged as an effective means of refining collections of information to minimize burden and improve utility. Tests must be approved if they call for answers to identical questions from 10 or more respondents. A proposed test or set of test may be submitted for approval separately or in combination with the main collection of information.

There are no tests of procedures or methods currently planned.

5. Provide the name and telephone number of individuals consulted on statistical aspects of the design and the name of the agency unit, contractor(s), grantee(s), or other person(s) who will actually collect and/or analyze the information for the agency.

The contact person for questions relating to the statistical aspects of the survey is Ms. Amy M. Newman-Smith. She can be reached on 301-763-6595. The contact person for questions relating to the collection and analysis of the data is Ms. Linnet Holland. She can be reached on 301-763-7647.