Demographic Multipliers: Recent National and State Findings Prepared By DAVID LISTOKIN, Ph.D. ROBERT W. BURCHELL, Ph.D. Prepared For NATIONAL IMPACT FEE ROUND TABLE (NIFR) NATIONAL CONFERENCE ARLINGTON, VIRGINIA OCTOBER 2006

PRESENTATION OVERVIEW Perspective on Demographic Multipliers: definition, application, and literature Changes in Multipliers Over Time Results of New National Data Results of New State Data (New Jersey example) Conclusions

DEFINITIONS OF DEMOGRAPHIC MULTIPLIERS Demographic multipliers – the number and profile of the populations associated with new residential and nonresidential development Residential multipliers – Resident population associated with housing Nonresidential multipliers – Worker population associated with commercial and other business uses

USE OF DEMOGRAPHIC MULTIPLIERS Interlinked Applications Impact fees Fiscal impact analysis School enrollment projections Public staffing analysis Market studies Calculating development standards “Cost of sprawl” studies Other applications

DEMOGRAPHIC MULTIPLIERS LITERATURE OVERVIEW (EXAMPLES) The Fiscal Impact Handbook (1978) The Practitioner’s Guide to Fiscal Impact Analysis (1985) Development Impact Assessment Handbook and Model (1994) Planner’s Estimating Guide (2004) Residential Demographic Multipliers (2006) Fiscal and Impact Fee Studies (1970s-2000s) Other Conclusion: Extensive literature—but of varying quality and dating is often an issue

U.S. RESIDENTIAL DEMOGRAPHIC MULTIPLIERS OVER TIME 1970 1990 2000 1970-2000 (Change) Single-Family (4BR) Household Size 4.67 3.70 3.53 -24% School children 1.92 1.18 1.01 -47% Town House (3BR) 4.07 2.69 2.55 -37% 1.33 0.53 0.44 -67% Garden Apartment (2 BR) 2.56 2.22 2.19 -14% 0.27 0.34 0.29 +0.7% Conclusion: There are generally significant decreases over time in household size and school children in most standard housing types. Current data is therefore essential.

Author: Center for Urban Policy Research, Rutgers University FANNIE MAE FOUNDATION (FMF) – RUTGERS RESIDENTIAL DEMOGRAPHIC MULTIPLIERS STUDY Author: Center for Urban Policy Research, Rutgers University Data: 2000 PUMS, U.S. Housing Constructed 1990-2000 Geography: All U.S., 50 States, and District of Columbia Release: Mid-2006 and available from FMF DataPlace™ (http://www.dataplace.org/newsarticle.html?aid=59)

Household size (HS) – Total persons per housing unit FANNIE MAE FOUNDATION (FMF) – RUTGERS RESIDENTIAL DEMOGRAPHIC MULTIPLIERS: DATA FIELDS (I) Multipliers comprise Household size (HS) – Total persons per housing unit Age distribution of household members – 0-4, 5-13, 14-17, 18-24, 25-44, 45-64, 65-74, 75+ Total school-age children (SAC) Total public school-age children (PSAC) SAC who attend public school SAC and PSAC by grade group – (K-2, 3-6, 7-9, 10-12, 9)

FANNIE MAE FOUNDATION (FMF) – RUTGERS RESIDENTIAL DEMOGRAPHIC MULTIPLIERS: DATA FIELDS (II) Multipliers Differentiated by: Housing Type Single-family detached Single-family attached 2-4 Unit 5+ Unit Mobile home Housing Size 1-5 bedrooms Housing Price (updated to 2005) All values Terciles (thirds): 1st – 33rd percentile, 34th – 66th percentile, 67th – 100 percentile Housing Tenure Ownership or rental

FANNIE MAE FOUNDATION (FMF) – RUTGERS RESIDENTIAL DEMOGRAPHIC MULTIPLIERS: SELECTED FINDINGS (I) Housing Type, Size, and Value U.S. Average Household Size (HS) Public School-Age Children (PSAC) Single-Family Detached, 3 BR All Values 2.84 0.51 1st-33rd percentile 3.01 0.69 34th-66th percentile 2.82 0.49 67th-100th percentile 2.73 0.40 Single-Family Detached, 4 BR 3.53 0.85 3.77 1.07 3.51 0.83 3.35

FANNIE MAE FOUNDATION (FMF) – RUTGERS RESIDENTIAL DEMOGRAPHIC MULTIPLIERS: SELECTED FINDINGS (II) Housing Type, Size, Value, and Tenure U.S. Average Household Size (HS) Public School-Age Children (PSAC) 5+ Units Own, 2 Bedrooms All Values 1.70 0.07 1st-33rd percentile 1.74 0.11 34th-66th percentile 1.68 0.06 67th-100th percentile 0.04 5+ Units Rent, 2 Bedrooms 2.19 0.27 2.25 0.34 2.23 2.10 0.18 Conclusion: Variations in demographics associated with housing type, housing size, housing value, and housing tenure.

FANNIE MAE FOUNDATION (FMF) – RUTGERS RESIDENTIAL DEMOGRAPHIC MULTIPLIERS: SELECTED FINDINGS (III) Housing Type and Size U.S. Average Household Size (HS) Age distribution 0-4 5-17 18-44 45-64 65+ Single-family Detached, 4BR 3.53 0.35 1.01 1.42 0.65 0.10 Single-family Attached, 2BR 1.93 0.12 0.17 0.82 0.46 0.36 Conclusion: Need to pay more attention to the age distribution of household members

NJ OFFICE OF SMART OF GROWTH (OSG) – RUTGERS DEMOGRAPHIC MULTIPLIERS STUDY Author: Center for Urban Policy Research, Rutgers University Data: 2000 PUMS, NJ Housing Constructed 1990-2000, Field studies and other Geography: NJ, All State and 3 regions Multiplier fields: HS, SAC and PSAC by housing type, size, value, tenure, and state region Statistics: Regression analysis of characteristics associated with variation in multipliers Multipliers presented with sample size, standard error, and confidence interval Other: affordable housing, transit oriented development (TOD), and nonresidential multipliers

Public School-Age Children (PSAC) OSG – RUTGERS RESIDENTIAL DEMOGRAPHIC MULTIPLIERS: SELECTED FINDINGS (I) Housing Type, Size, and Value NJ Average Household Size (HS) Public School-Age Children (PSAC) Single-Family Detached, 3 Bedroom All Values 2.977 0.484 Below median 3.038 0.542 Above median 2.913 0.423 Single-Family Attached, 2.655 0.381 2.823 0.491 2.444 0.244 Conclusion: Variation in demographics associated with housing type, housing size, and housing value (housing tenure and region)

OSG – RUTGERS RESIDENTIAL DEMOGRAPHIC MULTIPLIERS: SELECTED FINDINGS (II) NJ Average 90% Confidence Interval Housing Type, Size, and Value Public School-Age Children (PSAC) Low high Single-Family Attached, 2 Bedroom All Values 0.126 0.102 0.151 Below median 0.164 0.203 Above median 0.081 0.052 0.110 3 Bedroom 0.381 0.336 0.427 0.491 0.420 0.562 0.244 0.191 0.296 Conclusion: Variations around multiplier averages warrant heightened attention

Conclusion: What are appropriate multipliers for affordable housing? OSG – RUTGERS RESIDENTIAL DEMOGRAPHIC MULTIPLIERS: SELECTED FINDINGS (III) A. PUMS--Household Size and Public School-Age Children For Low- and Moderate-Income Households (LMI) in New Jersey (2000) Household Size (HS) Public School-Age Children (PSAC) All Housing Types and Bedrooms 2.35 0.45 Single-Family Attached 2 Bedroom 2.09 0.32 3 Bedroom 3.05 0.78 5+ Units, Rent 2.76 0.62 3.82 1.27 B. Case Study Investigation – Average PSAC for affordable housing units of 0.52—but range of 0.22 to 1.42 Conclusion: What are appropriate multipliers for affordable housing?

Transit Oriented Development (TOD) OSG – RUTGERS RESIDENTIAL DEMOGRAPHIC MULTIPLIERS: SELECTED FINDINGS (IV) Transit Oriented Development (TOD) Field investigation of 10 TODs with 2,200 housing units found they contained 50 public school-age children (PSAC)—or a PSAC multiplier of 0.02 per housing unit Application of standard residential multipliers (average 0.14 PSAC per unit) would have projected about 300 PSAC Conclusion: What are appropriate multipliers for emerging housing types such as TODs?

Conclusion: Need better data on nonresidential multipliers OSG – RUTGERS NONRESIDENTIAL DEMOGRAPHIC MULTIPLIERS: SELECTED EXAMPLES (V) Variation in nonresidential multipliers – retail example Employees per 1,000 ft.2 State of Washington (1998) 0.57 CBECS (2001) 0.83-1.95 CA Dept. Energy (1996) 1.70 ITE Trip Generation (1997) 2.00 Census of Retail (1997) 2.44 Conclusion: Need better data on nonresidential multipliers

DEMOGRAPHIC MULTIPLIERS CONCLUSION Critical data with many applications “Moving target” – changing figures over time Variations in residential demographic multipliers have been associated with such characteristics as housing type, housing size, housing value, and housing tenure Emerging areas of inquiry: Statistical analysis Household age distribution Emerging residential development categories Nonresidential multipliers