Construction of a SAM
This document describes the construction of a Social Accounting Matrix (SAM) for California. The SAM is a record of the transactions between institutions, such as consumers, firms, and government, for the calendar year 2003. It is based upon multiple sources, including input output tables, California tax and spending records, and California employment data. This SAM includes energy and uses The California Energy Balance Database (CALEB) for 2000, the most recent data available. There are also ancillary tables including the capital coefficients matrix, which records the uses of investment, and several miscellaneous tables which record tax system details, inter alia.
While the numbers in this SAM are wholly created from recent data, the SAM inherits its structure from the SAMs used for the Dynamic Revenue Analysis Model (DRAM).[1] This description borrows from the previous documentation, most heavily so in those areas where the new SAM inherits its structure from the previous SAM.
The SAM that will be described is the most complete description of transactions in 2003 in the State of California. It has been rectified to reflect the energy flows reported by EIA, by sector, and so provides the perfect base on which to construct models of the California economy. It is particularly suited to model the effects of pollution control and energy policy on California.
[1] Department of Finance, State of California, Summer 1996. http://134.186.99.249/html/fs_data/dyna-rev/dynrev.htm
Data Organization: Social Accounting Matrix
For the purposes of statistical description, the California economy is divided into 174 distinct sectors. Each sector is an aggregate. For industrial sectors, the aggregation is over closely related industries. So an industrial sector is a list of the aggregate purchases and sales of these related industries. Similarly, a consumer sector shows the income and expenditures of a group of consumers and a government sector shows the income and expenditures of a type of government.
A SAM is a square matrix consisting of a row and column for each sector of the economy. Each entry in the matrix identifies an exchange of goods and services purchased by one sector from another sector or itself. The entries along a row in the SAM show each payment received by that particular sector. Summing the data across the row gives the total of payments made to that sector. The entries down a column in the SAM show the expenditures made by a particular sector. Summing the data down a column gives the total expenditures by sector.
In this SAM California economy has been divided into a SAM composed of 174 distinct sectors: 108 industrial sectors, two factor sectors (labor, capital), eight household sectors, nine composite goods sectors, one investment sector, 45 government sectors, and one sector which represents the rest of the world. The design of the sectoring is an important element in the development of any CGE, Social-Accounting or IO model because it determines the flows that the model will be able to trace explicitly. If the sectoring is done well, the major flows in the economy, both positive and negative, will be evident. If the sectoring is done poorly, the impact of policy will be blurred, with negative and positive flows occurring within a single sector.
- Sectoring
Six sectoring categories will be discussed. The criteria for the sectoring of the SAM are presented and each sector is described in detail. The descriptions are highly technical and explain the sourcing and imputations necessary for each section of the SAM. The sectorings are:
1. Industrial Sectoring (uses the NAICS method to determine SAM sectors)
2. Factor Sectors (Capital and Labor)
6. The ROW SectorSource: Adapted from "Overview.doc" by Peter Berck, Ryan Kellogg, Lingyun Nie, and Stephen Stohs. 2003.
SAM Components
This section will describe the files that were compiled to construct the California SAM. The files are presented in the rough order that they are used beginning from raw data taken from the BEA and other available databases.
- 1997 US IO data
- ES 202 Dram Summary.xls
- v0304.xls
- G0304.xls
- PIT0304.xls
- CA Household Industry demand.xls
- HH Distn.xls
- GAMS Miscellaneous Data Inputs
- CCM0304.xls
- Energy data.xls
- ROW.xls
- SAM.xls
1. Database: 1997 US IO data
Purpose
This Access database produces 1997 US Make and Use tables for the SAM industrial sectors, using the 1997 US Make and Use data files (NAICS codes) and the mapping of NAICS codes to SAM sectors.
Raw data inputs:
· 1997 US Benchmark Make and Use data files, after redefinitions. Available from BEA. http://www.bea.gov/bea/dn2/i-o_benchmark.htm
Data inputs from other model workbooks:
- · Final mapping of NAICS codes to SAM sectors
- · Listing of SAM sectors with code numbers from 1 to 106
Outputs to:
· Generates two Excel files: Aggregate Use Matrix.xls and Aggregate Make Matrix.xls.
2. Workbook: ES 202 Dram Summary.xls
Purpose
This workbook generates sector by sector ratios of US 1997 wages to CA 2003 wages (e.g., the ratio of wages paid by the OILGAS sector to CA employees in 2003 to wages paid by OILGAS nationally in 1997). These ratios are ultimately used in the IO table (V0304.xls) to transform the 1997 US IO matrix to the CA 2003 IO matrix.
Raw data inputs:
- · California wage data (Q2 2002 – Q1 2003) from CA ES202 (Quarterly Census of Earnings and Wages)
- · CA employment by sector (Q2 2002 – Q4 2003) from CA CES (Current Employment Series)
- · BEA wage data for California and US
- o National: http://www.bea.gov/bea/dn/nipaweb/TableView.asp?SelectedTable=53&FirstYear=2003&LastYear=2004&Freq=Qtr
- o State: http://www.bea.gov/bea/regional/sqpi
Data inputs from other model workbooks:
- · National wages by industry from the 1997 US Use matrix (Aggregate Use Matrix.xls)
- · Final mapping of NAICS codes to SAM sectors
Outputs to:
- · IO Table calculations (V0304.xls, Aggregate Use Matrix.xls, Aggregate Make Matrix.xls)
3. Workbook: V0304.xls (also Aggregate Make Matrix.xls and Aggregate Use Matrix.xls)
Purpose
V0304.xls, Aggregate Make Matrix.xls, and Aggregate Use Matrix.xls together compute the CA 2003 IO table, for input into the SAM. The final result is located in V0304.xls. The Matlab routines LoadIO.m and CalcIOAggregate.m (add links) are also required.
Raw data inputs:
· None
Data inputs from other model workbooks:
- · Aggregate Make Matrix numbers.xls and Aggregate Use Matrix numbers.xls (output from the ‘1997 US IO Data.mdb’ Access database)
- · Worksheet of wage ratios from ‘ES 202 Dram Summary.xls’
Outputs to:
- · SAM.xls (the IO table copies to the ‘V0304’ worksheet in the SAM)
- · G0304.xls (the IO table copies to the worksheet ‘IO Table’)
- · CCM0304.xls (the CAPITAL row of the IO table feeds the ‘N0304’ worksheet)
Purpose
This workbook uses data regarding federal, state, and local government sectors to compute the government expenditure and revenue flows which appear in the SAM. The workbook consists of a top-level sheet (g0304) which displays the government sector portions of the SAM, and supporting sheets for federal (US0304), state (CA0304) and local governments (Local0304).
Raw data inputs:
- US0304 Sheet
- · Consolidated Federal Funds Report / FY 2002 (http://www.census.gov/govs/www/cffr.html)
- · DoD PRIME CONTRACT AWARDS By STATE and MAJOR PROCUREMENT PROGRAM ($) - FY2002 (http://web1.whs.osd.mil/peidhome/geostats/P06-P09/FY2002/P06-P09-State-Maj-Procurement-2002.xls)
- · Internal Revenue Service 2002 Data Book (http://www.irs.gov/pub/irs-soi/02databk.pdf)
- · California Budget Forecast, Nov. 2003
- · SUMMARY OF FEDERAL GOVERNMENT FINANCES: 1996 (used to allocate federal excise taxes; not updated from previous version)
- CA0304 Sheet
- · Governor’s Budget Forecast Appendix (http://www.dof.ca.gov/HTML/Budgt04-05/BudgetSum04/schds_04.pdf)
- o Schedule 8: Comparative Statement of Revenues
- o Schedule 9: Comparative Statement of Expenditures by Organization Unit, Character, Function and Fund
- Local0304 Sheet
- · Most recently available versions of various local government revenue and expenditure reports taken from the California State Comptroller’s Office web site (http://www.sco.ca.gov/pubs/index.shtml#localgovrep)
- o School Districts Annual Report (1999-00)
- o Community Redevelopment Agencies Annual Report (2001-02)
- o Counties Annual Report (2000-01)
- o Transit Operators and Non-Transit Claimants Annual Report (2001-02)
- o Special Districts Annual Report (1999-00)
- o Transportation Planning Agencies Annual Report (1997-98)
- o Street and Roads Annual Report (2001-02)
- o Cities Annual Report
Data inputs from other model workbooks:
· Payments to labor and capital from industry I/O matrix (V0304.xls)
Outputs to:
· SAM workbook
Purpose
This workbook generates all personal tax payments made by each household sector.
Raw data inputs:
- · California state tax data from 2000 (copied from old SAM)
- · 2003 Federal and CA personal income tax tables
- · 2003 federal income tax take from CA residents. (data from BEA, found in ‘CA personal income.xls’)
Data inputs from other model workbooks:
- · Total social security, local, and state tax take data from ‘g0304.xls’.
Outputs to:
- · SAM.xls (the sheet ‘Calcs’ copies directly over to the ‘PIT0304’ sheet in the SAM
- · CA Household Industry Demand.xls (the sheet ‘Calcs’ copies directly over to the ‘Tax data’ sheet, and the sheet ‘PIT relevant data’ copies directly over to ‘PIT relevant data’.
6. Workbook: CA Household industry demand.xls (and aggcons.xls)
Purpose
CA Household industry demand provides two main results: (1) it provides a breakdown of how much of each aggregate consumption good is produced by each SAM industrial sector, and (2) it calculates how much of each aggregate consumption good is consumed by each household type.
Raw data inputs:
- · Year 2000 CA consumption data from IMPLAN
- · CA personal income data from BEA
- · National personal income data from BEA (including personal saving)
Data inputs from other model workbooks:
- · Tax data from PIT0304.xls (copies of the ‘Calcs’ and ‘PIT relevant data’ worksheets)
Outputs to:
- · SAM.xls (the ‘Aggregate Industry Consumption’ sheet copies to ‘Indust prod’ in the SAM, and the ‘Aggregate Household Consumption’ sheet copies to ‘HH Agg Cons Raw’ in the SAM
- · g0304.xls (total HH demand by SAM industrial sector is copied to the ‘CA0304’ sheet of g0304.xls for the purpose of calculating sales tax.
7. Workbook: HHDistn.xls (missing)
Purpose
This workbook uses data from the 2002 California Census and the March 2002 Current Population Survey to approximate the aggregate numbers of households and working households by household type.
Raw data inputs:
- · Distribution of California Households by Income for 1999, from the 2002 California Census (hard copy in Giannini Library)
- · Table HINC-05. Percent Distribution of Households, by Selected Characteristics Within Income Quintile and Top 5 Percent in 2001, from March 2002 Current Population Survey (http://ferret.bls.census.gov/macro/032002/hhinc/new05_000.htm)
Outputs to:
· GAMS misc file
8. GAMS Miscellaneous Data Inputs (msc.xls)
Purpose
This file provides GAMS with various data tables needed to solve the model.
Data inputs from other model workbooks:
- · Household income distributions were calculated in HHDistn.xls
- · Tax parameters were computed in pit0304v8.xls
- · Employment by sectors were aggregated in ES 202 DRAM Summary 8.xls
- · Transfer payment estimates were taken from g0304.xls
Purpose
This workbook creates the capital coefficients matrix (CCM), which shows the percentage distribution of each industry sector’s investment in other industries. The entry in row i column j shows the percentage of sector j's investment which is made in sector i.
Raw data inputs:
· 1997 Capital Flow Table from the BEA
Inputs from other model workbooks:
· CA Wage data from Aggregate I/O Table workbook
Outputs to:
· GAMS CCM file
Purpose
‘Energy data’ is designed to correct the SAM transactions in energy sectors for the physical quantities of energy actually exchanged among sectors at the appropriate prices
Raw data inputs:
- · The California Energy Balance Database (CALEB) for 2000 (most recent year available).
- · PG&E natural gas and electric rates (see ‘Prices’ sheet for exact source)
- · Crude oil, gasoline, and wholesale natural gas prices from EIA (see ‘Prices’ sheet for exact source)
- · CA average wages from BLS (see ‘Prices’ sheet for exact source)
Data inputs from other model workbooks:
· Dollar transactions SAM from ‘SAM.xls’.
Outputs to:
· SAM.xls: the ‘To SAM’ sheet copies to the yellow box on the ‘Energy’ sheet in the SAM
Purpose
This workbook generates the ratios of industry exports to imports, using data from IMPLAN. These ratios are ultimately used to estimate exports and imports.
Raw data inputs:
- · CA export and import data from IMPLAN
Outputs to:
· SAM.xls (The ‘ROW’ worksheet copies to the ‘ROW’ worksheet of the SAM)
Purpose
The SAM workbook collects data from supporting files, storing them in separate worksheets, and combines them to form a balanced SAM.
Raw data inputs:
- · None
Data inputs from other model workbooks:
· V0304.xls, g0304.xls, CA Household industry demand.xls, PIT0304.xls, CCM0304.xls, Energy data.xls