Senate Staff Levels in Member, Committee, Leadership, and Other Offices, 1977-2016

Updated September 13, 2016 (R43946)
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Contents

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Tables

Summary

The manner in which staff are deployed within an organization may reflect the missions and priorities of that organization. This report provides staffing levels in Senators' Senate committee, leadership, and other offices since 1977. From 1977 to 1986, Senate staff, excluding state-based staff, increased from 3,397 to 4,180, or 23.05%. From 1987 to 2016, all Senate staff grew from 4,916 to 5,749, or 16.94%. The changes in both time periods were characterized in part by increases in the number of staff working in chamber leadership offices, and, prior to 2016, increases in the staffing of chamber officers and officials. Additionally, staff working for Members have shifted from committees to the personal offices of Members. Since 2010, however, staff working for the Senate has decreased 6.79%. Some of these changes may be indicative of the growth of the Senate as an institution, or the value the chamber places on its various activities.

This report is one of several CRS products focusing on congressional staff. Others include CRS Report RL34545, Congressional Staff: Duties and Functions of Selected Positions, by R. Eric Petersen; CRS Report R43947, House of Representatives Staff Levels in Member, Committee, Leadership, and Other Offices, 1977-2016, by R. Eric Petersen and Amber Hope Wilhelm; CRS Report R44324, Staff Pay Levels for Selected Positions in Senators' Offices, FY2001-FY2015, coordinated by R. Eric Petersen; CRS Report R44323, Staff Pay Levels for Selected Positions in House Member Offices, 2001-2015, coordinated by R. Eric Petersen; CRS Report R44322, Staff Pay Levels for Selected Positions in House Committees, 2001-2015, coordinated by R. Eric Petersen; and CRS Report R44325, Staff Pay Levels for Selected Positions in Senate Committees, FY2001-FY2015, coordinated by R. Eric Petersen.


The manner in which staff are deployed within an organization may reflect the missions and priorities of that organization.

In Congress, employing authorities hire staff to carry out duties in Member-office, committee, leadership, and other settings. The extent to which staff in those settings change may lend insight into the Senate's work over time. Some of the insights that might be taken from staff levels include

This report provides staffing levels in Senators',1 committee, leadership, and other offices since 1977. No Senate publication appears to officially and authoritatively track the actual number of staff working in the chambers by office or entity. Data presented here are based on staff listed by chamber entity (offices of Senators, committees, leaders, officers, officials, and other entities) in Senate telephone directories. Figure 1 displays overall staffing levels in the Senate.

Table 1 in the "Data Tables" section below provides data for all staff listed in chamber directories in the Senate through 2016. Joint committee staff data from the Senate for panels that met in the 114th Congress (2015-2016) are provided in Table 7.

Senate Staffing

Senate Staff Data Collection

This report provides data based on a count of staff listed in the Senate telephone directories published since 1977.2 Like most sources of data, telephone directory listings have potential benefits and potential drawbacks. Telephone directories were chosen for a number of reasons, including the following:

At the same time, however, data presented below should be interpreted with care for a number of reasons, including the following:

Senate Staff Data

It appears that the Senate telephone directories started listing Senate staff working in Senators' state offices in 1987. Given the lack of consistent staff data from Senators' offices prior to 1987, comparisons between data from those offices from 1977-1986 and 1987-2016, as well as any analysis of total staffing levels in the Senate before 1987, would be incomplete. Staff levels from committees, leadership, and officers and officials, however can be evaluated across the entire 1977-2016 time period. Additionally, analysis of total staffing levels, as well as staff distribution, since 1987 is discussed below.

In the Senate, the number of staff has grown steadily, from 4,916 in 1987 to 5,749 in 2016, or 16.94%. Each year since 1987, the number of Senate staff has grown by an average of 29 individuals,8 or 0.58%. From 1977 to 1986, excluding congressional staff from state offices, the number of staff in the Senate has grown steadily from 3,397 in 1977 to 4,180 in 1986, or 23.05%. Figure 1 displays staff levels in six categories (Senators' DC offices, Senators' state offices, total staff in Senators' offices, committees, leadership, and officers and officials) since 1977. Figure 2 provides the distributions among categories of offices from 1987 to 2016.

Table 1 in the "Data Tables" section, below, provides detailed staff levels in those categories.

Figure 1. Senate Staff Levels by Category, 1977-2016

Source: Senate telephone directories, CRS calculations.

Notes: All categories are based on a full count of directory listings.

Staff in Senators' Offices

Staff in Senators' offices grew from 2,068 in 1977 to 2,474 in 1986, or 19.63%. Due to the addition of staff in Senators' state offices, comparisons of total staff before 1986 to after are not possible. But staff in Senators' Washington, DC, offices continued to grow. In 2016, there were 2,342 staff in Senators' DC offices, an increase of 13.25% from the 1977 level, 2,068. Staff in Senators' offices, including state-based staff, have grown from 3,286 in 1987 to 4,120 in 2016, or 25.38%. Senators' office staffs have grown as a proportion of overall Senate staff over time. In 1987, Member-office staff comprised 66.84% of Senate staff. The proportion grew to 67.51% in 1990, and 72.96% in 2000, before dropping slightly to 71.66% in 2016.

Most of the growth in Senators' staffs since 1987 appears to have been among state-based staff, which nearly doubled in size from 935 in 1987 to 1,778 in 2016. More staff work in Washington, DC, offices than in state offices, but the percentage of Senators' staff based in states has grown steadily since 1987, while the number of staff in Senators' Washington, DC, offices has remained relatively flat. In 2016, 56.84% of staff listed in the Senate telephone directory as working in Senators' offices did so in Washington, DC, down from a high of 72.18% in 1988. Table 2 in the "Data Tables" section below provides the number of staff working in Senators' offices in Washington, DC, and state offices.

Committees

Senate committee staff levels have shown the smallest change among Senate staff categories, increasing from 1,084 in 1977 to 1,153 in 2016, or 6.37%. Change among Senate committee staff may be characterized in three stages: an increase during 1977-1980 (20.57%); a period of decline in 1980-1999 (-27.93%); and a period of growth from 1999 to 2016 (22.40%).

Between 1987 and 2016, committee staff comprised a decreasing proportion of Senate staff, falling from a peak of 23.39% of Senate staff in 1987 to a low of 17.49% of staff in 1995. The proportion of Senate committee staff grew to 20.06% in 2016, still below its 1987 peak.

In the "Data Tables" section below, three tables provide staff levels in various Senate committees. Table 3 provides data for 2007-2016; data for 1997-2006 are available in Table 4, Table 5 provides data for 1987-1996, and data for 1977-1986 are in Table 6. Totals for each year, which include Senate joint committee staff found in Table 7, are provided in Table 1.

Leadership Offices

The number of staff in Senate leadership offices grew from 44 in 1977 to 160 in 2016. The majority of the growth in leadership staff occurred between 1977 and 1981, from 44 to 119, or 170.45%. The number of leadership staff peaked in 2012 at 234. As a proportion of Senate staff, leadership employees were 2.69% in 1987 and 2.78% in 2016.

Officers and Officials

Staff working in the offices of Senate officers and officials has grown 57.21% since 1977. Staff levels have grown from 201 in 1977 to 316 in 2016, but were characterized by sharp decreases in 1988, from 1998-2001, in 2012, and in 2016.

Despite the growth, Senate officers and officials' staff decreased as a proportion of Senate staff, falling from 7.08% in 1987 to a low of 5.21% in 2012. In 2016, the proportion of officers and officials' staff was 5.50%.

Figure 2. Percentage of Senate Staff in Each Category, 1987-2016

Source: Senate telephone directories, CRS calculations.

Notes: All categories are based on a full count of directory listings.

Discussion

Since 1987, the number of staff working for the Senate has grown. There have been increases in the number of staff working in Senate leadership offices, and larger increases in the staffing of officers and officials through 2015, though 2016 saw a dip in those numbers. Staff working for Senators have shifted from committee settings to leadership settings or the personal offices. Some of these changes may be indicative of the growth of the Senate as an institution, or the value the chamber places on its various activities.

One example that may be an indication of institutional development arguably is found in the growth of the number of staff working in leadership and officers and officials' offices. A potential explanation for these changes may be found in what some might characterize as an ongoing professionalization and institutionalization of congressional management and administration. Some note that as organizations such as governing institutions develop, they identify needs for expertise and develop specialized practices and processes.9 In Congress, some of those areas of specialization arguably include supporting the legislative process through the drafting of measures, oversight and support of floor activities, and the management of legislation in a bicameral, partisan environment. Another potential explanation related to a more institutionalized, professionalized Congress could be the demands for professional management and support. This could arise as a result of congressional use of communications technologies, and the deployment of systematic, professionalized human resources processes, business operations, and financial management. Consequently, increased specialized support of congressional legislative and administrative activities may explain increases among staff working for chamber leaders, and officers and officials.

In another example, the distribution of staff working directly for Senators has shifted from committee settings to personal office settings. Staff in Member offices has grown while staff in Senate committees has decreased, both in real numbers and in percentage of total staff. This may represent a shift from collective congressional activities typically carried out in committees (including legislative, oversight, and investigative work) to individualized activities typically carried out in Senators' personal offices (including direct representational activities, constituent service and education, and political activity).10

Data Tables

Table 1. Senate Staff Levels by Category, 1977-2016

Year

1977

1978

1979

1980

1981

1982

1983

1984

1985

1986

Senators' Offices

2,068

2,215

2,173

2,296

2,308

2,385

2,454

2,430

2,409

2,474

Committee

1,084

1,244

1,209

1,307

1,161

1,228

1,200

1,191

1,137

1,177

Leadership

44

103

55

49

119

132

136

138

121

131

Officers and Officials

201

213

230

261

253

264

327

354

376

398

Totals

3,397

3,775

3,667

3,913

3,841

4,009

4,117

4,113

4,043

4,180

Year

1987

1988

1989

1990

1991

1992

1993

1994

1995

1996

Senators' Offices

3,286

3,393

3,354

3,445

3,612

3,707

3,593

3,826

3,771

3,773

Committee

1,150

1,147

1,167

1,174

1,176

1,216

1,141

1094

915

929

Leadership

132

133

138

144

146

156

147

163

157

156

Officers and Officials

348

276

350

340

321

362

425

393

388

353

Totals

4,916

4,949

5,009

5,103

5,255

5,441

5,306

5,476

5,231

5,211

Year

1997

1998

1999

2000

2001

2002

2003

2004

2005

2006

Senators' Offices

3,678

3,876

3,801

3,823

3,639

3,855

3,915

4,091

4,047

4,232

Committee

899

955

942

979

915

1,071

1,047

1,126

1,078

1,146

Leadership

166

162

166

159

154

166

176

167

193

220

Officers and Officials

353

280

282

279

260

282

309

315

297

325

Totals

5,096

5,273

5,191

5,240

4,968

5,374

5,447

5,699

5,615

5,923

Year

2007

2008

2009

2010

2011

2012

2013

2014

2015

2016

Senators' Offices

4,044

4,221

4,029

4,346

4,180

4,219

4,037

4,071

3,965

4,120

Committee

1,147

1,182

1,153

1,246

1,262

1,200

1,116

1,131

1,114

1,153

Leadership

204

182

175

180

126

234

164

158

177

160

Officers and Officials

326

361

372

396

372

311

379

398

381

316

Totals

5721

5946

5732

6168

5,940

5,964

5,696

5,758

5.637

5,749

Source: Senate telephone directories, CRS calculations.

Notes: All categories are based on a full count of directory listings. Senate telephone directories published in 1981, 1996, 2009, and 2013 provided listings for 99 Senators' offices. Before 1987, the Senate directories did not list congressional staff in Senators' state offices. Therefore, the staffing levels for "Senators' Offices", as well as the "Totals" from 1977 to 1986 do not reflect the same data as the years 1987 to 2016.

Table 2. Staff Working in Senators' Offices, 1977-2016

Year

DC-Based
Staff

State-Based
Staff

Total Member
Staff

DC %

State %

1977

2,068

 

 

 

 

1978

2,215

 

 

 

 

1979

2,173

 

 

 

 

1980

2,296

 

 

 

 

1981

2,308

 

 

 

 

1982

2,385

 

 

 

 

1983

2,454

 

 

 

 

1984

2,430

 

 

 

 

1985

2,409

 

 

 

 

1986

2,474

 

 

 

 

1987

2,351

935

3,286

71.55%

28.45%

1988

2,449

944

3,393

72.18%

27.82%

1989

2,381

973

3,354

70.99%

29.01%

1990

2,430

1,015

3,445

70.54%

29.46%

1991

2,439

1,173

3,612

67.52%

32.48%

1992

2,473

1,234

3,707

66.71%

33.29%

1993

2,332

1,261

3,593

64.90%

35.10%

1994

2,474

1,352

3,826

64.66%

35.34%

1995

2,422

1,349

3,771

64.23%

35.77%

1996

2,397

1,376

3,773

63.53%

36.47%

1997

2,318

1,360

3,678

63.02%

36.98%

1998

2,407

1,469

3,876

62.10%

37.90%

1999

2,375

1,426

3,801

62.48%

37.52%

2000

2,329

1,494

3,823

60.92%

39.08%

2001

2,258

1,381

3,639

62.05%

37.95%

2002

2,334

1,521

3,855

60.54%

39.46%

2003

2,378

1,537

3,915

60.74%

39.26%

2004

2,474

1,617

4,091

60.47%

39.53%

2005

2,436

1,611

4,047

60.19%

39.81%

2006

2,521

1,711

4,232

59.57%

40.43%

2007

2,394

1,650

4,044

59.20%

40.80%

2008

2,496

1,725

4,221

59.13%

40.87%

2009

2,370

1,659

4,029

58.82%

41.18%

2010

2,513

1,833

4,346

57.82%

42.18%

2011

2,417

1,763

4,180

57.82%

42.18%

2012

2,409

1,810

4,219

57.10%

42.90%

2013

2,321

1,716

4,037

57.49%

42.51%

2014

2,340

1,731

4,071

57.48%

42.52%

2015

2,257

1,708

3,965

56.92%

43.08%

2016

2,342

1,778

4,120

56.84%

43.16%

Source: Senate telephone directories, CRS calculations.

Notes: The Senate telephone directory did not provide listings for state-based staff prior to 1987. Senate telephone directories published in 1981, 1996, 2009, and 2013 provided listings for 99 Senators' offices.

Table 3. Senate Committee Staff by Committee, 2007-2016

Committee

2007

2008

2009

2010

2011

2012

2013

2014

2015

2016

Agriculture, Nutrition, and Forestry

30

35

32

43

37

39

33

30

34

33

Appropriations

124

121

116

114

119

113

115

125

127

133

Armed Services

51

53

49

50

49

51

45

48

50

49

Banking, Housing, and Urban Affairs

41

46

48

60

51

51

47

54

40

44

Budget

50

49

45

54

54

50

62

59

47

39

Commerce, Science, and Transportation

69

69

69

65

69

71

62

62

74

71

Energy and Natural Resources

42

44

47

52

54

51

54

47

43

50

Environment and Public Works

41

40

45

44

45

41

43

39

42

37

Finance

82

83

84

84

87

74

80

78

80

77

Foreign Relations

52

46

47

66

63

62

50

51

55

48

Health, Education, Labor, and Pensions

77

90

89

91

85

83

77

77

89

93

Homeland Security and Governmental Affairs

89

100

112

127

123

123

93

122

85

104

Judiciary

143

121

106

120

168

125

108

109

112

121

Rules and Administration

22

22

20

23

23

21

21

21

19

18

Small Business and Entrepreneurship

25

32

31

29

29

29

26

18

16

25

Veterans Affairs

24

25

26

27

22

21

22

20

18

20

Select Ethics

11

11

15

15

14

12

13

14

18

14

Indian Affairs

16

20

20

21

17

24

14

17

21

21

Select Intelligence

37

43

39

42

45

45

43

38

41

40

Select Aging

23

23

13

20

16

15

16

23

19

22

Source: Senate telephone directories.

Notes: Committees are listed by names used in the 114th Congress, or most recent year in which the committee existed. "-"indicates that no staff were listed for that year. In some instances this was because the committee did not exist. In other instances, a directory listing for a panel was identified, but did not list any staff.

Table 4. Senate Committee Staff by Committee, 1997-2006

Committee

1997

1998

1999

2000

2001

2002

2003

2004

2005

2006

Agriculture, Nutrition, and Forestry

26

27

23

27

22

32

27

33

22

29

Appropriations

63

61

87

89

102

90

101

118

120

118

Armed Services

45

45

43

47

44

51

47

48

46

48

Banking, Housing, and Urban Affairs

41

41

44

42

38

60

41

46

47

46

Budget

44

45

44

48

46

52

50

49

47

49

Commerce, Science, and Transportation

54

58

51

56

48

59

72

69

64

68

Energy and Natural Resources

40

38

37

40

38

43

42

42

46

43

Environment and Public Works

34

36

36

43

33

49

53

56

51

50

Finance

45

52

52

46

52

56

60

62

53

63

Foreign Relations

48

51

49

54

55

54

49

56

57

53

Health, Education, Labor, and Pensions

76

85

98

86

76

72

74

90

95

92

Homeland Security and Governmental Affairs

78

76

65

85

74

92

82

86

71

109

Judiciary

85

93

84

98

82

112

115

129

127

137

Rules and Administration

21

19

15

16

16

18

16

16

19

18

Small Business and Entrepreneurship

19

17

18

20

22

29

21

22

24

28

Veterans Affairs

21

38

19

16

18

19

20

17

22

23

Select Ethics

8

11

10

11

11

11

9

9

10

10

Indian Affairs

18

15

16

20

18

21

19

18

16

11

Select Intelligence

27

34

33

29

31

32

30

34

28

42

Select Aging

18

20

18

17

10

25

20

19

12

15

Select Year 2000 Technology Problem

-

-

15

-

-

-

-

-

-

-

Source: Senate telephone directories.

Notes: Committees are listed by names used in the 114th Congress, or most recent year in which the committee existed. "-"indicates that no staff were listed for that year. In some instances this was because the committee did not exist. In other instances, a directory listing for a panel was identified, but did not list any staff.

Table 5. Senate Committee Staff by Committee, 1987-1996

Committee

1987

1988

1989

1990

1991

1992

1993

1994

1995

1996

Agriculture, Nutrition, and Forestry

30

35

38

45

40

36

36

35

31

31

Appropriations

78

78

84

80

79

81

78

72

71

61

Armed Services

46

49

49

49

50

48

47

49

43

43

Banking, Housing, and Urban Affairs

34

31

44

49

50

51

49

48

40

42

Budget

61

61

54

58

58

55

56

52

46

39

Commerce, Science, and Transportation

76

75

72

70

70

72

73

67

59

61

Energy and Natural Resources

44

46

48

50

50

51

49

48

42

44

Environment and Public Works

46

47

48

50

47

47

37

39

37

37

Finance

54

54

54

54

58

57

49

49

47

53

Foreign Relations

54

57

57

51

69

67

66

58

47

51

Health, Education, Labor, and Pensions

95

107

104

102

106

102

93

108

81

79

Homeland Security and Governmental Affairs

88

92

97

92

93

96

96

86

61

63

Judiciary

101

100

98

111

105

119

106

106

86

93

Rules and Administration

29

27

27

28

27

28

27

25

18

18

Small Business and Entrepreneurship

22

20

21

22

21

21

19

22

19

20

Veterans Affairs

25

26

25

26

24

26

21

21

18

17

Select Ethics

9

7

9

11

11

10

11

12

11

9

Indian Affairs

23

41

26

23

22

28

20

20

14

16

Select Intelligence

38

40

41

40

40

41

32

36

24

30

Select Aging

24

26

30

32

33

32

26

23

16

20

Select POW/MIA Affairs

-

-

-

-

-

15

-

-

-

-

Select Impeachment Trials

-

-

2

-

-

-

-

-

-

-

Select Investigations

-

-

20

-

-

-

-

-

-

-

Select Iran-Contra

53

-

-

-

-

-

-

-

-

-

Source: Senate telephone directories.

Notes: Committees are listed by names used in the 114th Congress, or most recent year in which the committee existed. "-"indicates that no staff were listed for that year. In some instances this was because the committee did not exist. In other instances, a directory listing for a panel was identified, but did not list any staff.

Table 6. Senate Committee Staff by Committee, 1977-1986

Committee

1977

1978

1979

1980

1981

1982

1983

1984

1985

1986

Agriculture, Nutrition, and Forestry

28

37

30

35

33

34

35

32

33

32

Appropriations

69

67

74

89

63

76

81

81

80

82

Armed Services

28

29

27

27

36

34

37

39

42

42

Banking, Housing, and Urban Affairs

39

49

43

46

38

39

33

29

29

31

Budget

47

79

67

77

63

70

73

74

68

63

Commerce, Science, and Transportation

89

91

83

92

77

88

78

78

80

78

Energy and Natural Resources

40

51

52

55

49

52

49

51

48

48

Environment and Public Works

30

33

38

38

52

51

54

51

49

50

Finance

28

34

36

40

45

50

45

53

54

55

Foreign Relations

63

57

55

68

62

62

61

62

60

61

Health, Education, Labor, and Pensions

93

122

118

121

118

123

123

112

101

105

Homeland Security Governmental Affairs

108

153

140

156

113

121

120

117

94

99

Judiciary

119

144

139

153

120

135

116

119

121

126

Rules and Administration

27

30

30

31

30

32

29

28

29

28

Small Business and Entrepreneurship

22

21

23

23

22

23

24

21

22

21

Veterans Affairs

18

19

20

23

20

22

22

20

21

25

Select Ethics

2

9

15

12

17

13

12

10

8

8

Indian Affairs

0

25

26

15

13

14

19

20

19

23

Select Intelligence

40

46

43

46

41

41

41

36

32

47

Select Aging

19

19

19

21

28

28

25

34

25

27

Select Nutrition and Human Needs

14

-

-

-

-

-

-

-

-

-

Select Senate Committee Systems

5

-

-

-

-

-

-

-

-

-

Select Transition Staff for Former Postal Workers

13

-

-

-

-

-

-

-

-

-

Source: Senate telephone directories.

Notes: Committees are listed by names used in the 114th Congress, or most recent year in which the committee existed. "-"indicates that no staff were listed for that year. In some instances this was because the committee did not exist. In other instances, a directory listing for a panel was identified, but did not list any staff.

Table 7. Staff of Active Joint Committees Listed in the Senate Directories, 1977-2016

Joint Committee

1977

1978

1979

1980

1981

1982

1983

1984

1985

1986

Economic

46

51

53

58

46

43

44

44

40

39

Library of Congress

-

-

2

2

2

2

3

3

3

3

Printing

15

15

16

16

15

16

16

17

17

16

Taxation

-

63

60

63

58

59

60

60

62

68

Joint Committee

1987

1988

1989

1990

1991

1992

1993

1994

1995

1996

Economic

35

45

44

43

41

44

45

29

35

32

Library of Congress

2

2

2

2

2

2

2

2

2

1

Printing

17

17

14

16

14

14

17

16

7

8

Taxation

66

64

59

70

66

73

73

71

60

61

Joint Committee

1997

1998

1999

2000

2001

2002

2003

2004

2005

2006

Economic

23

25

23

31

21

34

35

36

31

31

Library of Congress

-

-

-

-

-

-

2

2

2

2

Printing

9

8

-

-

1

2

2

4

4

4

Taxation

56

60

62

58

57

58

60

65

64

57

Joint Committee

2007

2008

2009

2010

2011

2012

2013

2014

2015

2016

Economic

35

35

34

34

29

37

30

17

21

31

Library of Congress

4

4

-

-

-

-

-

-

-

-

Printing

4

4

-

-

-

-

-

-

-

-

Taxation

55

66

66

65

63

62

62

62

63

63

Source: Senate telephone directories.

Notes: Individual staff members for the joint committees may appear in both the House and the Senate directories, as they are considered neither solely House nor solely Senate staff. They are included where they appear in the directory. Excludes staff listed at various times since 1977 for the Joint committees on Inaugural Ceremonies, Atomic Energy, Defense Production, Internal Revenue Service, and Organization of Congress. Staff data for those panels are available to congressional clients from the authors upon request. "-"indicates that no staff were listed in the relevant chamber for that year. In some instances, a directory listing for a panel was identified, but did not list any staff.

Author Contact Information

R. Eric Petersen, Specialist in American National Government ([email address scrubbed], [phone number scrubbed])
Amber Hope Wilhelm, Visual Information Specialist ([email address scrubbed], [phone number scrubbed])

Acknowledgments

Lara Chausow, former Research Assistant, was a coauthor of this report and collected some of the data provided.

Footnotes

1.

Throughout this report, the terms "Member office," "personal office," and "Senator's office" refer to the office held by a Senator as a consequence of election or appointment to the Senate. They do not refer to the number of facilities in which that work is carried out. Discussions of how many staff are based in Washington, DC, and state facilities distinguish only between locations in Washington, DC, or in the state. It does not provide an office-by-office accounting of staff working in multiple state facilities.

2.

Senate directories listed some Washington, DC-based staff assigned to specific entities (e.g., Member, committee, and other offices) in 1958. The House first published a directory with detailed staff listings by entity in 1977.

3.

The actual moment is the deadline that was set for the final collection of listings prior to publication. The exact date for each year is not known, but publication dates for the House and Senate directories were generally in the spring of each year.

4.

Other congressional documents list staff by organizational unit, most notably the quarterly Statement of Disbursements issued by the House, and the semiannual Report of the Secretary of the Senate, issued by the Senate. At the same time, because they capture all paid staff activity for a three-month (House Statements) or six-month (Senate Reports) period, those documents do not provide as clear a picture of staffing at one point in time as the telephone directories.

5.

In the Senate telephone directories, for example, state-based staff in Senators' offices were not listed until 1987. This omission is likely to lead to an undercount of Senate staff prior to 1987.

6.

In some instances, a listing for a Senate entity would not list staff. In other instances, there were significant changes in the number of staff from year-to-year, and it could not be determined whether that was a consequence of changing organizational practices, or differences in the manner in which staff were included in the directory.

7.

For example, some congressional staff may work on a part-time basis for more than one Member, or for a Member and a committee. In limited instances (some commissions and joint committees), it is possible that some staff are listed in both House and Senate directories.

8.

Rounded to reflect a whole number.

9.

See, for example, Nelson W. Polsby, "The Institutionalization of the U.S. House of Representatives," The American Political Science Review, vol. 62, no. 1 (March 1968), pp. 144-168.

10.

See CRS Report RL33686, Roles and Duties of a Member of Congress: Brief Overview, by R. Eric Petersen; CRS Report RL34035, Grants Work in a Congressional Office, by Julie Jennings and Maria A. Kreiser and CRS Report RL33209, Casework in a Congressional Office: Background, Rules, Laws, and Resources, by R. Eric Petersen.