conversion to the 1987 standard industrial classification · appendix b. conversion to the 1987...
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Appendix B. Conversion to the 1987 Standard Industrial Classification
Effective with the publication of August 1990 data, all industry employment,hours, and earnings series were converted to 1987 Standard Industrial Classifica-tion (SIC) codes.1 This new structure replaces the 1972 SIC coding structure in ef-fect since 1978, for the industry estimates derived from the establishment survey.
The SIC coding system is periodically updated to reflect structural and techno-logical changes in the economy. Growing, emerging industries may be recognizedwith independent SIC codes for the first time, while SIC codes for declining indus-tries may be eliminated by collapsing them with other like industries into a singleSIC code. The 1987 SIC revision marks the first full SIC restructuring since 1972;there were minor updates to the SIC system in 1977.
Scope of the SIC restructuring. Approximately two-thirds of the published industryseries were unaffected by the SIC revision. There were almost no changes in scopeat the major industry division levels, with only very minor shifts between whole-sale and retail trade and between the finance, insurance, and real estate divisionand services. However, there were several significant redefinitions at the 2-digitlevel. The most notable were in two divisions, manufacturing and services. Inmanufacturing, a substantial realignment took place between electronic and otherelectrical equipment (SIC 36) and instruments and related products (SIC 38). Rubberand miscellaneous plastics products (SIC 30) and stone, clay, and glass products(SIC 32) were also noticeably affected, but to a much lesser degree. In services, anew 2-digit code (SIC 87) was established for "engineering and management ser-vices." Most of these activities had previously been classified in business services(Sic 73) or miscellaneous services (Sic 89).
At the 3- and 4-digit SIC levels, changes in scope were both more prevalent andmore substantial. Table B-l lists all 1987 Sic-based published series which are notequivalent to a 1972 Sic-based series and relates them to the 1972-based seriesfrom which they were derived. Ratios indicate the percentage of employment ineach old series that was allocated to the new series. Table B-l also lists the begin-ning year that all-employee data are available for each of these series. Table B-2lists the 44 previously published 1972-based industry series which were deleted in
1 As defined in the 1987 Standard Industrial Classification Manual, issued by the Executive Officeof the President, Office of Management and Budget.
the conversion to the 1987 SIC structure. It indicates which 1987-based series thesewere converted to and the percentage of employment from the old series whichwent to each new series. It should be noted that, in addition to industry stratifica-tion changes required by the SIC redefinitions, some changes were made to im-prove estimating efficiencies.
Reconstruction of estimates. All restructured industries were reestimated using the1987 sic-coded sample data from January 1988 forward. Some aggregate level in-dustries, without scope changes, were also affected by the retabulations becausethey are formed from the summation of restratified, reestimated component in-dustries.
Historical estimates prior to 1988 could not be retabulated from sample data,because sample records provided only 1972 SIC codes. For industries with rela-tively minor scope changes, historical data were reconstructed back to the incep-tion of the series, wherever possible. The reconstruction of historical series wasdone by adjusting the existing 1972-based employment series for the percentage ofemployment lost or the percentage of employment gained from other industries,using ratios derived from first quarter 1988 universe employment data. The firstquarter 1988 data represent the only dual Sic-coded data available for developingthese adjustment ratios.2
Hours and earnings data for restructured series were derived by computing aweighted average of the component series they were derived from. The weights arethe percentages of employment each old series contributed to the new series.
Effects due to SIC restructuring. As indicated in table B-3, the SIC revision had alarge impact on only a few major industries. For total nonfarm employment, theSIC revision effect, due entirely to restratification and not to any change in scope,was 56,000 or less than 0.05 percent. At the major division levels, the impact var-ied from 1,000 in mining to 65,000 in services. Almost all of the effect at the majordivision levels was also from the restratification of industries within these aggre-gates, not from sic scope changes. At the detailed industry level, the largest effectsof the SIC revision were in business services (-928,000), instruments and related
2 For additional information, see Employment Data Under the New Standard Industrial Classification,First Quarter 1988, Report 772, October 1989.
673
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March 1991
products (+301,000), and electronic and other electrical equipment (-292,000).There were few significant changes at the published aggregate levels.
Among average weekly hours estimates, only transportation and public utilitiesshowed a significant effect from recomputation, a downward revision of 0.6 hour.Among average hourly earnings series, both electronic and other electrical equip-ment and instruments and related products showed large, partially offsettingchanges, due to sic redefinitions. Other differences were much less significant. Atthe total private level, hours and earnings were unchanged (table B-3).With re-
spect to seasonally adjusted data, all published series were revised for the mostrecent 5 years (1985-90) for the incorporation of new seasonal factors, as is usual.In addition, series affected by the SIC revision which were reconstructed for yearsprior to 1985 have again been seasonally adjusted, based on the 1987 sic-basedestimates.
For additional information on the SIC revision and its effect on published series,see Patricia M. Getz, "BLS Establishment Estimates Revised to March 1989 Bench-marks and 1987 SIC Codes," Employment and Earnings, September 1990, pp 6-34.
674
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March 1991
Table B-1. Published industries restructured under the 1987 SIC and relationship of employment to the 1972 SIC industries
1987 SIC industry1987SIC
code
1972SIC
code
1972 to 1987ratio1
Beginningyear
for all-employee
series
Mining:Bituminous coal and lignite mining
Construction:Heavy construction, except building
Highway and street constructionHeavy construction, except highway
Special trade contractors
Manufacturing:Durable goods
Lumber and wood products
Millwork, plywood, and structural members
Millwork
Miscellaneous wood products
Furniture and fixtures:Office furniture
Partitions and fixtures
Miscellaneous furniture and fixtures
Stone, clay, and glass products
Pottery and related products
Miscellaneous nonmetallic mineral products
Primary metal industries:Aluminum foundries
Fabricated metal products
Cutlery, handtools, and hardware
Hand and edge tools, and blades and handsaws
Plumbing and heating, except electric
Plumbing fixture fittings and trim
Heating equipment, except electricFabricated structural metal products
Metal doors, sash, and trim
See footnotes at end of table.
122
161611621621717
24242424324324312431249249
252252254254259
3232326326329
3365
34343434342342
3423,53423,5
3433433432343234333443443442
12
161611611621617
24342624334424313442249266
252259254259259
3236326367329
3361
34353730342355
3423,53555343307343230734333443463442
94.6666
96.521484.75113.2454
100.00003.4785
100.0000
299.68733.9717
100.0000.5094.6518
100.00001.7230
100.00008.9878
100.000064.8231
100.00002.1165
100.00001.6588
96.2246
94.5041.0816
100.0000.2680
72.6864
55.6354
99.4321.0018.3067.3849
100.0000.0229
100.0000.1363
98.5898.5265
100.0000.5265
95.931898.2769.9996
91.0121
1939
197219881972
1972
1939
1947
1972
1972
1972
1958
1958
1958
1939
1947
1988
1988
1947
1947
1972
1972
1972
19721972
1958
675
Digitized for FRASER http://fraser.stlouisfed.org/ Federal Reserve Bank of St. Louis
March 1991
Table B-1. Published industries restructured under the 1987 SIC and relationship of employment to the 1972 SIC industries—Continued
1987 SIC industry1987SIC
code
1972SIC
code
1972 to 1987ratio1
Beginningyear
for all-employee
series
Fabricated metal products—ContinuedSheet metal work
Metal forgings and stampingsMetal stampings, nee
Miscellaneous fabricated metal products
Valves and pipe fittings, nee
Industrial machinery and equipment
Construction machinery
Industrial trucks and tractors
Metalworking machinery
Special industry machinery
Printing trades machineryFood products machinery
General industrial machinery
Pumps and pumping equipmentSpeed changers, drives, and gears
Computer and office equipment
Electronic computersComputer terminals, calculators, and office machines, nee .
Refrigeration and service machinery
Refrigeration and heating equipment
Miscellaneous industrial and commercial machinery
Scales, balances, and industrial machinery, nee
Electronic and other electrical equipment
Electric distribution equipmentSwitchgear and switchboard apparatus
3444346
3469349349
3494
35353535
3531353135373537
354354354355355355
35553556
356356356
35613566
357357
35713575,8,93575,8,93575,8,93575,8,9
358358
35853585359359359359
3596,93596,9
3636
3613613
3444346
3469349372
3494
34353637
3531353635363537
354356362354355363
35553551
343355356
35613566
357366
357335733574
3572,93661358369
35853699356357359372
35763599
3536
3613613
91.851499.000397.1998
100.0000.8923
37.7579
.058499.4217
.8759
.7329100.000024.64233.0149
100.000098.77863.79837.46761.2213
90.80781.1304
87.055065.6950
1.41017.0169
87.853561.960990.107696.8416
.416672.28303.9089
100.0000100.0000
2.1568100.0000
.3433100.0000
4.32738.34801.4144
100.00002.1324
100.000093.9304
.401884.240595.925891.8226
1958197219721972
1988
1947
1972
1972
1958
1958
195819881972
198819721958
19881988
1958
1972
1972
1982
1939
19581958
See footnotes at end of table.
676
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March 1991
Table B-1. Published industries restructured under the 1987 SIC and relationship of employment to the 1972 SIC industries—Continued
1987 SIC industry1987SIC
code
1972SIC
code
1972 to 1987ratio1
Beginningyear
for all-employee
series
Electronic and other electrical equipment—ContinuedElectrical industrial apparatus
Relays and industrial controls
Household appliances
Electric lighting and wiring equipment
Electric lamps
Communications equipmentTelephone and telegraph apparatus
Electronic components and accessoriesElectron tubes
Electronic components, neeMiscellaneous electrical equipment and supplies . .
Transportation equipmentAircraft and parts
Aircraft parts and equipment, nee . . .
Instruments and related products
Search and navigation equipment
Measuring and controlling devices
Medical instruments and supplies
Costume jewelry and notionsMiscellaneous manufactures
Nondurable goods
Food and kindred products:Poultry slaughtering and processing.
Preserved fruits and vegetablesCanned specialtiesPrepared feeds, nee
3623623623625362536253633643643641364136636613661367367136713679369369369369
373723728
3838381381382382382382384384396399399
20152015203203220482048
3613623673613362236793633643693641369936636613662367
3671-336793679357366367369
373723728
3638366381366381382383369384396396399
20162017203203220472048
4.074192.5323.84338.1773
100.00002.057498.8695100.0000
.8295100.000010.455046.991697.84315.759297.2806100.00001.891855.45041.74395.15371.6079
78.1093
98.960296.975287.9661
14.8019100.000047.102762.9508.3350
37.0491100.0000100.000020.7178100.000085.802614.1973100.0000
2.3127399.0283
100.0000100.000095.888399.839220.1742100.0000
1958
1972
19581958
1972
19881988
19581988
19881988
193919391972
1947
1988
1988
1988
19881972
1939
1972
197219721972
See footnotes at end of table.
677
Digitized for FRASER http://fraser.stlouisfed.org/ Federal Reserve Bank of St. Louis
March 1991
Table B-1. Published industries restructured under the 1987 SIC and relationship of employment to the 1972 SIC industries—Continued
1987 SIC industry1987SIC
code
1972SIC
code
1972 to 1987ratio1
Beginningyear
for all-employee
series
Food and kindred products—ContinuedBakery products
Cookies, crackers, and frozen bakery products, except breadSugar and confectionery products
Candy and other confectionery productsMiscellaneous food and kindred products
Textile mill products:Knitting mills
Yarn and thread mills:Yarn spinning mills
Throwing and winding mills
Miscellaneous textile goods
Apparel and other textile products:Men's and boys' shirts
Men's and boys' trousers and slacks
Men's and boys' work clothing
Paper and allied productsPaper mills
Sanitary food containersFolding paperboard boxes
Paper, coated and laminated, neeBags: plastics, laminated, and coated
Printing and publishing:Commercial printing
Commercial printing, nee
Printing trade services
Chemicals and allied products:Industrial inorganic chemicals
Industrial inorganic chemicals, nee
Industrial organic chemicalsIndustrial organic chemicals, nee
Rubber and miscellaneous plastics products
205205
2052,3206206206
2064209209
225225
2281228122822282
229
2321232523252326
26262262
26562657265726722673
27527592759279279
281281
28192819
2862869
303030
203205
2038203206209
2065203209
225229
2281228322822283229
2321232723282328
26262266
26542651265426412643
27527512753275279
281286
28192861,9
2862861,9
323530
3.5699100.0000100.0000
.5247100.0000
.735689.1262
.016999.2643
100.00005.3622
100.000081.6835
100.000018.113594.6377
93.9364100.000044.831755.1683
99.3481100.000035.176869.2511
100.000030.748970.368863.3756
99.0699100.000075.3906
.9300100.0000
100.0000.1290
100.0000.1621
99.870996.9608
5.4958.1745
99.6150
1972
19881972
19881972
1958
1972
1972
1958
19581988
1988
19391972
19881988
19881988
19581972
1972
1972
1972
19721972
1939
See footnotes at end of table.
678
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March 1991
Table B-1. Published industries restructured under the 1987 SIC and relationship of employment to the 1972 SIC industries—-Continued
1987 SIC industry1987SIC
code
1972SIC
code
1972 to 1987ratio1
Beginningyear
for all-employee
series
Rubber and miscellaneous plastics products—ContinuedHose, belting, gaskets, and packing
Rubber and plastics hose and belting
Fabricated rubber products, nee
Miscellaneous plastics products, nee
Transportation and public utilties:Transportation
Water transportationWater transportation of freight, nee
Water transportation services
Air transportation, scheduled
Freight transportation arrangement
Communications and public utilities
Radio and television broadcastingTelevision broadcasting stations
Cable and other pay television service
Electric, gas, and sanitary services
Sanitary services
Wholesale trade
Durable goods
Motor vehicles, parts, and supplies
Motor vehicle supplies and new partsConstruction materials, nee
Professional and commercial equipment
Computers, peripherals and softwareElectrical goods
Electrical apparatus and equipmentElectronic parts and equipment
Machinery, equipment, and supplies
Industrial machinery and equipment
Miscellaneous wholesale trade durable goods
See footnotes at end of table.
3053053052
306306306308
44444444449449451451473473
48,4948,4948348334844844949495495
50-5150-51
50505015015013503950450450455065063506550850850845084509509
329303,4303,4
355303,4306307
44443,4445445446451452471472
48,4948,4948348334834894449446495
50-5152-59
50595015935013503950450850815065063506550650850635084504509
27.313596.960895.8367
2.15223.3092
100.000099.4734
499.956799.234888.6249.6366
76.299698.5600100.000054.5385100.000021.6219
100.00004.0433
96.198092.43513.801975.7386.7651
100.00001.4399
100.0000
100.0000.1156
100.0000.9010
100.000028.027894.731143.956331.424048.034855.422198.880971.3835100.00001.1190
51.96512.1547
100.000068.5759100.0000
1972
1972
1972
1958
196419641988
1988
1988
1988
1964
195819821988
1964
1972
1939
1972
1972
198219881988
19881958198819881982
1982
1988
679
Digitized for FRASER http://fraser.stlouisfed.org/ Federal Reserve Bank of St. Louis
March 1991
Table B-1. Published industries restructured under the 1987 SIC and relationship of employment to the 1972 SIC industries—Continued
1987 SIC industry1987SIC
code
1972SIC
code
1972 to 1987ratio
Beginningyear
for all-employee
series
Retail tradeDepartment storesMiscellaneous general merchandise stores
Automotive dealers, nee
Radio, television, and electronic stores
Record and prerecorded tape stores
Miscellaneous retail establishmentsFuel dealersRetail stores, nee
Finance, insurance, and real estateFinance
Depository institutions
Commercial banksState commercial banks
Savings institutions
Savings institutions, except Federal
Credit unions
Nondepository institutions
Personal credit institutions
Business credit institutions
Commodity contracts brokers, dealers, and exchanges .Security and commodity services
Insurance
Insurance agents, brokers, and services
Real estate
Real estate agents and managers
Services
Personal services
See footnotes at end of table.
52-59531539539
5595731
5735
59598599599
60-65,6760-62,6760-62,67
6060602602260226036036036036603660366036606
6161614614615615615
622,3628
63,6463,64
64646565653653
72
52-59531531539
556,95732
5733
59598598599
60-6760-62,67
66
60616026022
6023,460260361260226036123
6124,5614
616661466615
611,366
622,3,8622,3,8
63646466656665366
72
99.884497.35422.6457
100.0000
32.520566.2163
64.8882
99.098999.4440.5559
100.0000
99.9972100.00004.7158
100.000059.165898.564997.350196.10981.4350
100.0000100.00002.6498
100.0000100.0000100.000048.2236
40.83414.699051.77633.242199.432338.63891.4632
29.497973.7368
100.0000100.0000100.000056.2094100.000037.2352100.000037.36845.0028
5100.000090.7985
193919581988
19881988
1988
197219581972
19391972
1988
19721988
1988
1988
1988
1988
1988
1972
19881988
1972
1972
1972
1972
1939
1958
680
Digitized for FRASER http://fraser.stlouisfed.org/ Federal Reserve Bank of St. Louis
March 1991
Table B-1. Published industries restructured under the 1987 SIC and relationship of employment to the 1972 SIC industries—Continued
1987 SIC industry1987SIC
code
1972SIC
code
1972 to 1987ratio1
Beginningyear
for all-employee
series
Personal services—ContinuedLaundry, cleaning, and garment services
Miscellaneous personal services
Business services
Personnel supply servicesHelp supply services
Prepackaged softwareData processing and preparation
Miscellaneous business services
Detective and armored car services
Motion pictures
Amusement and recreation services
Miscellaneous amusement and recreation services
Health services:Offices and clinics of medical doctors
Offices and clinics of dentists
Nursing and personal care, neeHome health care services
Legal services
Social services:Individual and family services
Museums and botanical and zoological gardens
Engineering and management services
Research and testing services
Management and public relations
Services, nee
721721729
737373673637363737273747387387381
78787979799799799
8018018028028059808
8181
8328328484878787387387487489
721725,9725,9
727373673627369737273747357397393
73787279
725,9793
791,9
8018088028088059809
6681
8328397984738973989273673989
100.0000.7028
56.8650
1.635482.431496.4391100.000054.521628.466074.5430100.000050.796591.8657
1.8798100.00007.566099.270131.62863.833090.9632
100.000038.9567100.0000
.267047.088781.4568
1.8565100.0000
100.000030.4147.7298
100.000015.688697.758816.7540100.00003.560820.57572.2411
1972
1988
1958
19721982
198819881988
1982
1988
1988
1988
1972
1982
19881988
1972
1988
1988
1988
1988
1988
1988
1 Based on microdata files of dual-coded industries for first quarter 1988.2 A small portion of durable goods was reassigned to nondurable goods.3 A small portion of nondurable goods was reassigned to durable goods.4 A small portion of transportation was reassigned to communications and public utilities.
5 Services under the 1987 SIC structure comprise all of the 1972-SIC based components plus a very smallportion of finance, insurance, and real estate.
NOTE: Nee is an abbreviation for "not elsewhere classified" and designates broad categories of indus-tries which cannot be more specifically identified.
681
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March 1991
Table B-2. Disposition of employment in industries deleted from the 1987 SIC structure
1972 SIC industry1972SIC
code
1987SIC
code
Dispositionin
1987 SIC
Coal mining
Crude petroleum, natural gas, and natural gas liquids
Aluminum foundries
Food products machinery
Electronic computing equipment.
Machinery, except electrical, nee
Industrial controls
Radio and TV communication equipment
11,12
131,2
3361
3551
3573
3599
3622
3662
Optical instruments and lenses .
Poultry dressing plants
Cookies and crackers
Cane and beet sugar
Confectionery products
Men's and boys' separate trousers
Men's and boys' work clothing
Paper and pulp mills
Paper coating and glazing
Bags, except textile bags
See footnotes at end of table.
383
2016
2052
2061,2,3
2065
2327
2328
261,2,6
2641
2643
12
131132
33633365
35563565
35713572
3575,8,93577
3695,9
35933599
3625
366136633669
3695,938123829
382
2015
2052,3
206120622063
20642068
2325
23252326
261262249
26712672
26732674
100.0000
97.62032.3797
44.364655.6354
65.695034.3050
72.28307.36033.9089
14.46591.9818
6.069693.9304
100.0000
5.759224.26164.79486.3878
58.3813
.4153
100.0000
100.0000
100.000032.995426.306340.6983
89.126210.8738
100.0000
44.831755.1683
7.568490.12702.3046
29.631270.3688
63.375636.6244
682
Digitized for FRASER http://fraser.stlouisfed.org/ Federal Reserve Bank of St. Louis
March 1991
Table B-2. Disposition of employment in industries deleted from the 1987 SIC structure—Continued
1972 SIC industry1972SIC
code
1987SIC
code
Dispositionin
1987 SIC
Folding paperboard boxes .
Sanitary food containers ..
Commercial printing, letterpress
Gum, wood, and industrial organic chemicals, nee
Reclaimed rubber, and rubber and plastics hose and belting
Miscellaneous plastics products
Trucking and trucking terminals
Local water transportation ,
Water transportation services .
Air transportation
Freight forwarding
Commercial machines and equipment.
Professional equipment and supplies .
Car dealers
Radio and television stores .
Music stores .
State banks, not Federal Reserve
Savings and loan associations . . .
State associations, insured
See footnotes at end of table.
2651
2654
2751
2861,9
303,4
307
421,3
445
446
451,2
471
5081
5086
551,2
5732
5733
6023,4
612
6123
2657
26562657
2759
286128192869
305306
308343
421423
444448449
449495
451452
4731
504450455046504750485049
551552
57315734
57355736
60226036603
6036
100.0000
69.251130.7489
100.0000
4.2875.1621
95.5505
96.96083.0392
99.4735.5265
99.6780.3220
.636722.100777.2626
98.56011.4399
96.67383.3262
100.0000
35.618655.42218.9593
65.066611.896923.0366
94.12895.8711
66.216333.7837
64.888235.1118
96.10983.8902
100.0000
100.0000
683
Digitized for FRASER http://fraser.stlouisfed.org/ Federal Reserve Bank of St. Louis
March 1991
Table B-2. Disposition of employment in industries deleted from the 1987 SIC structure—Continued
1972 SIC industry1972SIC
code
1987SIC
code
Dispositionin
1987 SIC
Combined real estate, insurance, etc.
Temporary help supply services
Miscellaneous business services
Management and public relations.
Detective and protective services.
Equipment rental and leasing
Outpatient care facilities
66
7362
739
7392
7393
7394
808
61646581
7363
735738784873874
87328741874287438748
73817382
735373597841
801802809
4.699056.209437.2352
1.8565
100.0000
7.140650.79654.7332
16.754020.5757
16.689441.189426.79125.79549.5347
91.86578.1343
15.359744.777739.8626
38.9567.2671
60.7762
NOTE: Nee is an abbreviation for "not elsewhere classified" and designates broad categories of indus-tries which cannot be more specifically identified.
684
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March 1991
Table B-3. The SIC revision effect on nonfarm employment, hours, and earnings, March 1989
Industry
Employment 1
1972 SIC-based
estimate
1987 SIC-based
estimateDifference
Average weekly hours 2
1972 SIC-based
estimate
1987 SIC-based
estimateDifference
Average hourly earnings 3
1972 SIC-based
estimate
1987 SIC-based
estimateDifference
TotalTotal private
MiningConstructionManufacturing
Durable goodsNondurable goods
Transportation and public utilities . .Wholesale tradeRetail tradeFinance, insurance, and real estateServices
Government
107,01789,052
7024,837
19,55611,5508,0065,6076,154
19,0596,723
26,41417,965
107,07389,108
7034,813
19,58511,5388,0475,6466,145
19,0236,714
26,47917,965
5656
1-2429124139-9
-36-965
0
34.442.037.441.041.739.939.237.928.535.832.4
34.442.137.440.941.739.938.637.928.535.732.4
0.0.1.0
-.1.0.0
-.6.0.0
-.1.0
$9.5613.1513.2610.4110.939.66
12.4610.216.489.439.29
$9.5513.1713.3210.4110.949.66
12.4710.236.479.409.27
$-0.01.02.06.00.01.00.01.02
-.01-.03-.02
1 The largest effects of the SIC revision on nonfarm employment were in business services (-928,000),instruments and related products ( + 301,000), and electronic and other electrical equipment (-292,000),not shown separately.
2 The largest effect of the Sic revision on average weekly hours was in transportation and public
utilities (-0.6 hour).3 The largest effects of the sic revision on average hourly earnings were in instruments and related
products ( + .53 cents) and electronic and other electrical equipment (-.31 cents), not shown separately.
685
Digitized for FRASER http://fraser.stlouisfed.org/ Federal Reserve Bank of St. Louis
March 1991