California Department of Resources Recycling and Recovery (CalRecycle) 

Local Government Central

Adjustment Method Factors

Note: This page contains historical information from CalRecycle’s statewide goal measurement prior to 2007 that estimated a diversion percentage. For 2007 and subsequent years, CalRecycle compares reported disposal tons to population to calculate per capita disposal expressed in pounds/person/day. This new goal measurement system is described in CalRecycle’s Goal Measurement: 2007 and Later web page.

What is the Adjustment Method?

The "adjustment method" is a formula for annually estimating jurisdiction solid waste tons generated. Chapter 1292, Statutes of 1992 (Sher, AB 2494) required the Board to develop a standard methodology so that jurisdictions would have a cost-effective way to estimate how much waste they generate (see Public Resources Code 41780.1). Title 14, California Code of Regulations (14 CCR), Chapter 9, Article 9.1, requires that population, employment, taxable sales, and Consumer Price Index be used in the adjustment method formula. For more information about the adjustment method, see Adjustment Method Questions and Answers, or Board-Approved Adjustment Method and Goal Measurement.

Population

Population is used in the adjustment method because it strongly influences residential waste generation. Every ten years the U.S. Census Bureau counts the number of people living in each California city and county. The most recent census count was done in 2000. The California Department of Finance (DOF) estimates city and county January 1st population for the years between Census counts, e.g., 1991-1999 and 2001-2009. The CalRecycle's Electronic Annual Report (EAR) uses population data from DOF’s E-1: City/County Population Estimates with Annual Percent Change January 1, 2011 and 2012, released in May each year. For 1990-1999 population data, see Revised Historical City, County and State Population Estimates, 1991-2000, with 1990 and 2000 Census Counts. Jurisdictions may use either jurisdiction- or county-level population when estimating waste generation tons, then a diversion rate.

Employment

Employment strongly influences both residential and nonresidential waste generation. There are two distinct types of employment data. Labor force employment, also known as civilian employment, is the number of people living in a geographic area that have at least one job. Industry employment is the number of jobs in a geographic area. The California Employment Development Department (EDD) estimates both labor force and industry employment for each California county. Jurisdictions may use either county-level labor force or industry employment when estimating waste generation tons, then a diversion rate.

Taxable Sales

Taxable Sales strongly influences both residential and nonresidential waste generation. Taxable sales is the dollar amount of all transactions subject to California Sales and Use Tax. The State Board of Equalization (BOE) reports quarterly and annual taxable sales for each California city and county. Jurisdictions may use either jurisdiction- or county-level taxable sales when estimating waste generation tons, then a diversion rate.

Consumer Price Index and Taxable Sales Deflator

The Consumer Price Index (CPI) is a measure of inflation experienced by consumers and is an important indicator of the condition of the economy. CPI is used in the adjustment method to adjust taxable sales for inflation. The U.S. Department of Labor, Bureau of Labor Statistics (BLS), releases CPI for three metropolitan areas in California: (1) San Francisco/Oakland/San Jose, (2) Los Angeles/Anaheim/Riverside, and (3) San Diego. Subsequently, the California Department of Industrial Relations (DIR) uses a weighted average of the San Francisco/Oakland/San Jose and Los Angeles/Anaheim/Riverside metropolitan CPIs to compute a California Statewide CPI. All of this CPI data is available on the DIR website. Jurisdictions may use either their metropolitan area (where applicable) or statewide CPI when estimating waste generation tons, then a diversion rate.

Board research in 2004 indicates that BOE’s Taxable Sales Deflator (TSD) is a more accurate measure of inflation for taxable sales. TSD is a measure of inflation only for items subject to California Sales and Use Tax. CPI measures inflation of all consumer goods and services, regardless of whether they are subject to California Sales and Use Tax. For a more detailed discussion of the differences between TSD and CPI, see BOE’s February 2004 issue of Economic Perspective. TSD is only available at the statewide level. In September 2005, the Board directed staff to allow jurisdictions to use the Board's Taxable Sales Deflator Index (TSDI) as an acceptable alternative to CPI for diversion rate calculations.

Adjustment Method Formula

Note: Step-by-step instructions and automated calculations are available in the Model Annual Report.  Also available is a step-by-step written description of the adjustment method formula.

Formula:

[Estimated Reporting Year Generation] =
    [Base Year Residential Waste Generation Tons] x [Residential Adjustment Factor]  +
    [Base Year Nonresidential Waste Generation Tons] x [Nonresidential Adjustment Factor]

[Residential Adjustment Factor] = [(PR/PB)  + {ER/EB + (CB/CR x TR/TB)}/2 ] / 2

[Nonresidential Adjustment Factor] = [ER/EB + (CB/CR x TR/TB)] / 2

Adjustment Factors:

PR = Reporting Year Population   PB = Base Year Population
ER = Reporting Year Employment EB = Base Year Employment
CR = Reporting Year Consumer Price Index CB = Base Year Consumer Price Index
TR = Reporting Year Taxable Sales TB = Base Year Taxable Sales

Diversion Rate Measurement Home | Basics: Adjustment Factors Jurisdiction Default Adjustment Factors

Last updated: May 4, 2012
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Local Assistance & Market Development: LAMD@calrecycle.ca.gov (916) 341-6199