# Presentation: 915321

- Greg Harper
- Population Division
- September 28, 2006
- Presented to FSCPE Fall Meeting

- Reviewing Subcounty Population Estimates

## Overview

- Subcounty population estimates methodology
- Review of housing unit data
- Review of subcounty population estimates

**Notes:**
The Manufacturing and Construction Division stopped collecting demolition data after 1994

1993 cinch survey, regional numbers of hu loss by age and type.  A risk value was developed and applied to the census hu stock 

##  Subcounty Population Estimates Methodology

**Distributive Housing Unit Method**

- Change in housing units since the last Census at the subcounty level is used to distribute the estimated county population

- Components of Housing Unit Change
-  Residential Construction
-  Mobile Home Placements
-  Housing Unit Loss

**Notes:**
The Place and County Subdivision population estimates are produced using the Distributive Housing Unit Method.
This method uses the change in the housing units at the subcounty level to distribute the estimated county population to the subcounty level.

There are three components of housing unit change
1) residential construction
2) mobile home placements
3) housing unit loss

Subcounty group quarters is taken from the same source as the county group quarters data

## Housing Unit Estimates Equation

**HU****06**** = HU****00**** + (NC****06**** + NM****06****) –**** ****HL****06**
- HU06 = Estimated 2006 Housing Units
- HU00  = 2000 Housing Unit Estimates Base
- NC06 = Estimated New Residential Construction: 2000 - 2006
- NM06 = Estimated New Residential Mobile Homes: 2000 - 2006
- HL06 = Estimated Residential Housing Loss: 2000 - 2006

**Notes:**
This is the basic housing unit equation used for 1996:

HU96 = HU90 + (NC96 + NM96) - HL96

The Estimated 1996 Housing Units equals;
the 1990 Census Housing Unit Count plus;
the Estimated Residential Construction, from 4/1/90-7/1/96 plus;
the Estimated New Residential Mobile Home Placements, from 4/1/90-7/1/96 minus;
the Estimated Residential Housing Loss, 4/1/90-7/1/96

## Estimated Residential Construction

- Building Permits
- Compiled by the Census Bureau’s manufacturing and Construction Division (MCD)
- Nonpermitted Construction
- Estimated from annual Survey of Construction

**Notes:**
The Manufacturing and Construction Division stopped collecting demolition data after 1994

1993 cinch survey, regional numbers of hu loss by age and type.  A risk value was developed and applied to the census hu stock 

##   Mobile Home Placements

- State mobile shipments data distributed to subcounty areas based on the subcounty area’s share of mobile homes in Census 2000
- Sample data retabulated for consistency with 100 percent housing unit data

**Notes:**
This is the basic housing unit equation used for 1996:

HU96 = HU90 + (NC96 + NM96) - HL96

The Estimated 1996 Housing Units equals;
the 1990 Census Housing Unit Count plus;
the Estimated Residential Construction, from 4/1/90-7/1/96 plus;
the Estimated New Residential Mobile Home Placements, from 4/1/90-7/1/96 minus;
the Estimated Residential Housing Loss, 4/1/90-7/1/96

##  Housing Unit Loss 

- Data derived from 1997–2003 AHS National Sample
- Type of Non-interview Considered a Loss
- Type B, 16 - Interior exposed to the elements
- Type C, 30 – Demolished or disaster loss
- Type C, 31 – House or mobile home moved
- Categories for Developing Loss Rates
- Mobile Homes
- Age of Structure (seven categories)

**Notes:**
The Manufacturing and Construction Division stopped collecting demolition data after 1994

1993 cinch survey, regional numbers of hu loss by age and type.  A risk value was developed and applied to the census hu stock 

## Summary of Loss Rates

- 0.295% Total Annual Loss Rate
- Mobile Homes: 1.580%
- Houses or Apartments
- 1990-2000: 0.058%
- 1980-1990: 0.092%
- 1970-1980: 0.100%
- 1960-1970: 0.178%
- 1950-1960: 0.224%
- 1940-1950: 0.359%
- Pre-1940:   0.395%

**Notes:**
The Manufacturing and Construction Division stopped collecting demolition data after 1994

1993 cinch survey, regional numbers of hu loss by age and type.  A risk value was developed and applied to the census hu stock 

## Uncontrolled Subcounty Population Estimate

**UHHP****06**** = HU****06 ***** OCC****00**** * PPH****00**
- UHHP06 = Uncontrolled 2002 subcounty household population estimate
- HU06 = 2006 Housing Unit Estimate
- OCC00 = Census 2000 occupancy rate
- PPH00 = Census 2000 population per household

## Final Subcounty Population Estimate

**SCPOP****06**** = [UHHP****06 ***** (ARCHHP****06****/HUMHHP****06****)]  + GQ****06**
- SCPOP06 = Final 2006 subcounty population estimate
- UHHP06  = Uncontrolled 2006 household population estimate
- ARCHHP06 = 2006 Administrative Records method county household population estimate
- HUMHHP06 = 2006 Housing Unit method county household population6 estimate
- ARCHHP06/HUMHHP06 = Rake Factor
- GQ06 = 2006 group quarters population estimate

## The Housing Unit Review File

- File contains components of housing unit change
- Available in late October
- Two months of review
- Can be made available to local governments
- Data for areas affected by Katrina

## Housing Unit Review File Components

- PER7_2005 = building permits issued in calendar year 2004 * .98
- Assumes six-month lag time between permit issuance and completed construction
- Assumes 2 percent of permits do not result in completed construction

## Housing Unit Review File Components

- MOB7_2005 = New mobile homes allocated to  place from July 1, 2004 to July 1, 2005
- NPHB7_2005 = Nonpermitted residential construction allocated to place from July 1, 2004 to July 1, 2005
- If permits are issued for locality, NPHB will be 0

## Housing Unit Review File Components

- NPHD7_2005 = Estimated housing unit loss from July 1, 2004 to July 1, 2005
- The same loss rate is applied to updated estimates of housing units so the amount of loss will not change much from year to year
- HSG7_2005 = 2005 estimate of housing units
- HSG7_2005 = HSG7_2004 + PER7_2005 + MOB7_2005 + NPHB7_2005 – NPHD7_2005

## Housing Unit Review

- Use Excel spreadsheet in same format
- Keep housing units consistent with components
- Route local comments through FSCPE agency
- Provide comments in lowest level of geography
- Summary level 157 in non-MCD states, 071 in MCD states

**Notes:**
The Manufacturing and Construction Division stopped collecting demolition data after 1994

1993 cinch survey, regional numbers of hu loss by age and type.  A risk value was developed and applied to the census hu stock 

## The Subcounty Population Estimates Review File

- File will be made available In February
- Three to four weeks for review
- File can _**not be shared with local governments**_

## Subcounty Population Estimates Review File 

- VACR_2000 = Census 2000 Vacancy Rate
- PPH_2000 = Census 2000 Population per Household
- HU_2005 = 2005 Housing Unit Estimate
- GQ_2005 = 2005 Group Quarters Population Estimate

## Subcounty Population Estimates Review File 

- HHPOP_2005 = 2005 subcounty population estimate
- HHPOP_2005 = HU_2005 * PPH_2000* ((100 – VACR_2000)/100) * RAKE_2005
- POPCEN_2000 = Census 2000 total population
- PBASE_2000 = 2000 Estimates base population
- Census 2000 population updated with County Question Resolution Actions, boundary changes, and administrative geographic revisions.

## Subcounty Population Estimates Review File

- POP_2005 = HHPOP_2005 + GQ_2005
- RAKE_2005 = County population estimate/ county sum of uncontrolled subcounty housing unit population estimates
- A rake factor less than 1 indicates faster housing unit growth than population growth

## Subcounty Population Estimates Review

- Comments should be as specific as possible
- Most changes should have already been made to the housing unit file
- If housing units are OK and the county estimate is OK then problems should be limited to GQ or calculations

## Questions ?