National Academies Press: OpenBook

Population Dynamics of Senegal (1995)

Chapter: Appendix B: Correcting the Fertility Estimates in the 1988 Census

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Suggested Citation:"Appendix B: Correcting the Fertility Estimates in the 1988 Census." National Research Council. 1995. Population Dynamics of Senegal. Washington, DC: The National Academies Press. doi: 10.17226/4900.
×

Appendix B
Correcting the Fertility Estimates in the 1988 Census

The 1988 census [18] questionnaire contained a single question to women about their births in the last 12 months. Unfortunately, because of mistakes in coding and processing, these data were not published in official census publications, and to this day, fertility estimates from the 1988 census remain unpublished. In an attempt to resolve this problem, members of the working group traveled to Senegal to work for a week on a team with officials from the Government of Senegal's Directorate of Statistics. The team analyzed the programs used to construct the fertility rates and reviewed the program used to clean the data before the final data analysis began. The Directorate of Statistics also made available to the team the raw data for a 10-percent sample in one department (Fatick) so that it could be carefully scrutinized.

The team identified the major problem to be that blank entries in the coded data were subject to two interpretations: blanks could signify either that there were no data for the women or that the women had not had a birth in the last 12 months. On closer examination, the team found that:

  • Boys and girls had been coded separately on the 1988 census data file. If either the number of boys or the number of girls was recorded as a blank on the data file, the program calculating the fertility rates excluded the birth(s) of the other sex.

  • If both entries were blank, the responses were treated as 0,0 (i.e., no boys, no girls).

Suggested Citation:"Appendix B: Correcting the Fertility Estimates in the 1988 Census." National Research Council. 1995. Population Dynamics of Senegal. Washington, DC: The National Academies Press. doi: 10.17226/4900.
×

The team used the 10 percent sample of Fatick to examine the importance of these findings for the fertility rates. They discovered that although the interviewers were supposed to have recorded the number of boys and girls born to all women in the 12 months before the census, the responses were missing for many women. Missing data were coded as two blank entries. There were also a considerable number of cases where one column contained data and the other was blank. Furthermore, the distribution of blank entries varied by the age of the women (with older and younger women having higher-than-average levels), but there seemed to be an underlying level of blank entries across all ages.

Based on this analysis, the age-specific fertility rates (ASFRs) were then reestimated using two methods: (1) assuming none of the blanks were missing births, and (2) assuming all of the blanks were missing births. At the national level, the interpretation of the blank entries altered the estimate of the total fertility rate (TFR) by approximately 0.3 of a birth. Although the difference in ASFRs between the two methods was not large, it confirmed the team's earlier finding that there was a distinct pattern to the blanks in the coded data. Subsequently, the ASFRs for each department were adjusted by the smallest ratio of [ASFR(ALL)/ASFR(NONE)], which was taken as the best estimate of the underlying level of nonresponse π in that department. Hence, the best estimate of the ASFRs in each region became:

Adjusted ASFR = π * ASFR (NONE)

These adjusted ASFRs are provided in Tables B-1 through B-11.

TABLE B-1 Age-Specific Fertility Rates, National, 1988 Census

 

Place of Residence

Age Group

Urban

Rural

Total

10-14

0.005

0.016

0.012

15-19

0.075

0.193

0.142

20-24

0.203

0.295

0.254

25-29

0.253

0.288

0.274

30-34

0.242

0.244

0.243

35-39

0.182

0.153

0.164

40-44

0.083

0.074

0.078

45-49

0.024

0.028

0.026

50-54

0.009

0.013

0.012

Suggested Citation:"Appendix B: Correcting the Fertility Estimates in the 1988 Census." National Research Council. 1995. Population Dynamics of Senegal. Washington, DC: The National Academies Press. doi: 10.17226/4900.
×

TABLE B-2 Age-Specific Fertility Rates, Dakar, 1988 Census

 

Department

Age Group

Dakar

Pikine

Rufisque

Region

Total

 

 

 

 

10-14

0.003

0.006

0.005

0.004

15-19

0.048

0.086

0.068

0.063

20-24

0.147

0.233

0.206

0.182

25-29

0.202

0.284

0.278

0.238

30-34

0.206

0.264

0.259

0.236

35-39

0.161

0.200

0.205

0.179

40-44

0.078

0.094

0.117

0.088

45-49

0.021

0.025

0.024

0.023

50-54

0.006

0.013

0.005

0.009

Urban

 

 

 

 

10-14

0.003

0.006

0.004

0.004

15-19

0.048

0.086

0.049

0.063

20-24

0.147

0.233

0.178

0.184

25-29

0.202

0.284

0.252

0.241

30-34

0.206

0.264

0.248

0.235

35-39

0.161

0.200

0.207

0.182

40-44

0.078

0.094

0.107

0.088

45-49

0.021

0.025

0.024

0.023

50-54

0.006

0.013

0.004

0.009

Rural

 

 

 

 

10-14

0.007

0.007

15-19

0.125

0.125

20-24

0.285

0.284

25-29

0.344

0.343

30-34

0.286

0.286

35-39

0.199

0.198

40-44

0.142

0.142

45-49

0.026

0.026

50-54

0.008

0.008

NOTE: —, not applicable

Suggested Citation:"Appendix B: Correcting the Fertility Estimates in the 1988 Census." National Research Council. 1995. Population Dynamics of Senegal. Washington, DC: The National Academies Press. doi: 10.17226/4900.
×

TABLE B-3 Age-Specific Fertility Rates, Diourbel, 1988 Census

 

Department

Age Group

Bambey

Diourbel

Mbacké

Region

Total

 

 

 

 

10-14

0.015

0.015

0.013

0.014

15-19

0.159

0.150

0.147

0.152

20-24

0.263

0.268

0.259

0.263

25-29

0.270

0.281

0.265

0.271

30-34

0.218

0.231

0.231

0.227

35-39

0.127

0.141

0.136

0.135

40-44

0.054

0.060

0.057

0.057

45-49

0.025

0.025

0.025

0.025

50-54

0.020

0.006

0.012

0.013

Urban

 

 

 

 

10-14

0.010

0.009

0.006

0.008

15-19

0.084

0.098

0.102

0.098

20-24

0.216

0.218

0.222

0.220

25-29

0.288

0.249

0.257

0.257

30-34

0.249

0.236

0.240

0.240

35-39

0.198

0.162

0.131

0.156

40-44

0.087

0.073

0.065

0.072

45-49

0.011

0.019

0.028

0.021

50-54

0.013

0.008

0.008

0.009

Rural

 

 

 

 

10-14

0.016

0.020

0.014

0.016

15-19

0.166

0.191

0.156

0.167

20-24

0.266

0.306

0.266

0.274

25-29

0.268

0.301

0.266

0.274

30-34

0.214

0.228

0.228

0.223

35-39

0.120

0.126

0.138

0.129

40-44

0.050

0.051

0.056

0.053

45-49

0.026

0.029

0.024

0.026

50-54

0.021

0.005

0.013

0.014

Suggested Citation:"Appendix B: Correcting the Fertility Estimates in the 1988 Census." National Research Council. 1995. Population Dynamics of Senegal. Washington, DC: The National Academies Press. doi: 10.17226/4900.
×

TABLE B-4 Age-Specific Fertility Rates, Fatick, 1988 Census

 

Department

Age Group

Fatick

Foundiougne

Gossas

Region

Total

 

 

 

 

10-14

0.006

0.013

0.010

0.009

15-19

0.181

0.192

0.164

0.179

20-24

0.336

0.321

0.301

0.320

25-29

0.330

0.323

0.302

0.319

30-34

0.283

0.274

0.257

0.272

35-39

0.212

0.172

0.181

0.191

40-44

0.081

0.074

0.067

0.075

45-49

0.034

0.022

0.029

0.030

50-54

0.012

0.010

0.012

0.011

Urban

 

 

 

 

10-14

0.001

0.004

0.007

0.004

15-19

0.063

0.086

0.122

0.091

20-24

0.277

0.281

0.258

0.271

25-29

0.304

0.302

0.290

0.299

30-34

0.262

0.287

0.271

0.272

35-39

0.211

0.208

0.209

0.210

40-44

0.062

0.078

0.047

0.059

45-49

0.030

0.006

0.023

0.023

50-54

0.017

0.007

0.007

0.011

Rural

 

 

 

 

10-14

0.006

0.014

0.010

0.010

15-19

0.201

0.203

0.172

0.192

20-24

0.344

0.324

0.308

0.327

25-29

0.333

0.325

0.304

0.321

30-34

0.285

0.273

0.254

0.272

35-39

0.212

0.168

0.176

0.189

40-44

0.083

0.073

0.070

0.077

45-49

0.035

0.024

0.031

0.031

50-54

0.012

0.010

0.012

0.012

Suggested Citation:"Appendix B: Correcting the Fertility Estimates in the 1988 Census." National Research Council. 1995. Population Dynamics of Senegal. Washington, DC: The National Academies Press. doi: 10.17226/4900.
×

TABLE B-5 Age-Specific Fertility Rates, Kaolack, 1988 Census

 

Department

Age Group

Kaffrine

Kaolack

Nioro du Rip

Region

Total

 

 

 

 

10-14

0.022

0.013

0.028

0.020

15-19

0.212

0.141

0.246

0.194

20-24

0.294

0.246

0.331

0.285

25-29

0.280

0.264

0.314

0.283

30-34

0.223

0.221

0.245

0.227

35-39

0.131

0.154

0.142

0.142

40-44

0.062

0.059

0.065

0.062

45-49

0.024

0.023

0.021

0.023

50-54

0.013

0.012

0.014

0.013

Urban

 

 

 

 

10-14

0.018

0.007

0.001

0.008

15-19

0.139

0.083

0.095

0.089

20-24

0.281

0.202

0.271

0.212

25-29

0.236

0.249

0.253

0.248

30-34

0.230

0.212

0.222

0.215

35-39

0.113

0.169

0.172

0.163

40-44

0.040

0.062

0.084

0.062

45-49

0.020

0.025

0.030

0.025

50-54

0.005

0.013

0.006

0.011

Rural

 

 

 

 

10-14

0.023

0.020

0.030

0.024

15-19

0.216

0.212

0.255

0.227

20-24

0.295

0.305

0.335

0.308

25-29

0.282

0.280

0.317

0.292

30-34

0.223

0.231

0.246

0.231

35-39

0.133

0.136

0.140

0.136

40-44

0.063

0.056

0.063

0.061

45-49

0.024

0.021

0.021

0.023

50-54

0.013

0.011

0.015

0.013

Suggested Citation:"Appendix B: Correcting the Fertility Estimates in the 1988 Census." National Research Council. 1995. Population Dynamics of Senegal. Washington, DC: The National Academies Press. doi: 10.17226/4900.
×

TABLE B-6 Age-Specific Fertility Rates, Kolda, 1988 Census

 

Department

Age Group

Kolda

Sédhiou

Vélingara

Region

Total

 

 

 

 

10-14

0.021

0.019

0.024

0.020

15-19

0.237

0.226

0.245

0.234

20-24

0.318

0.302

0.306

0.309

25-29

0.283

0.270

0.283

0.278

30-34

0.221

0.218

0.225

0.221

35-39

0.135

0.132

0.131

0.133

40-44

0.066

0.066

0.061

0.065

45-49

0.024

0.029

0.024

0.027

50-54

0.016

0.011

0.008

0.012

Urban

 

 

 

 

10-14

0.015

0.008

0.006

0.012

15-19

0.151

0.096

0.204

0.151

20-24

0.287

0.320

0.302

0.298

25-29

0.300

0.293

0.322

0.305

30-34

0.251

0.231

0.260

0.250

35-39

0.168

0.186

0.158

0.171

40-44

0.060

0.103

0.078

0.073

45-49

0.022

0.06

0.021

0.030

50-54

0.018

0.007

0.006

0.013

Rural

 

 

 

 

10-14

0.023

0.019

0.026

0.022

15-19

0.256

0.232

0.250

0.243

20-24

0.325

0.301

0.306

0.310

25-29

0.280

0.269

0.279

0.275

30-34

0.213

0.217

0.220

0.217

35-39

0.127

0.129

0.128

0.128

40-44

0.068

0.064

0.059

0.064

45-49

0.024

0.028

0.024

0.026

50-54

0.016

0.011

0.009

0.012

Suggested Citation:"Appendix B: Correcting the Fertility Estimates in the 1988 Census." National Research Council. 1995. Population Dynamics of Senegal. Washington, DC: The National Academies Press. doi: 10.17226/4900.
×

TABLE B-7 Age-Specific Fertility Rates, Louga, 1988 Census

 

Department

Age Group

Kébémer

Linguère

Louga

Region

Total

 

 

 

 

10-14

0.013

0.018

0.012

0.014

15-19

0.155

0.196

0.133

0.157

20-24

0.259

0.275

0.254

0.261

25-29

0.251

0.278

0.278

0.269

30-34

0.203

0.241

0.259

0.235

35-39

0.107

0.141

0.157

0.136

40-44

0.053

0.071

0.071

0.065

45-49

0.018

0.023

0.023

0.022

50-54

0.009

0.015

0.016

0.013

Urban

 

 

 

 

10-14

0.002

0.004

0.006

0.005

15-19

0.065

0.107

0.078

0.080

20-24

0.204

0.238

0.218

0.220

25-29

0.259

0.285

0.289

0.285

30-34

0.213

0.265

0.282

0.271

35-39

0.138

0.178

0.201

0.190

40-44

0.053

0.074

0.086

0.080

45-49

0.007

0.021

0.025

0.022

50-54

0.000

0.007

0.012

0.010

Rural

 

 

 

 

10-14

0.015

0.019

0.015

0.016

15-19

0.162

0.204

0.155

0.172

20-24

0.263

0.278

0.270

0.270

25-29

0.251

0.277

0.274

0.266

30-34

0.202

0.238

0.247

0.228

35-39

0.106

0.138

0.141

0.127

40-44

0.053

0.070

0.065

0.062

45-49

0.019

0.023

0.023

0.021

50-54

0.010

0.016

0.017

0.014

Suggested Citation:"Appendix B: Correcting the Fertility Estimates in the 1988 Census." National Research Council. 1995. Population Dynamics of Senegal. Washington, DC: The National Academies Press. doi: 10.17226/4900.
×

TABLE B-8 Age-Specific Fertility Rates, Saint-Louis, 1988 Census

 

Department

Age Group

Dagana

Matam

Podor

Region

Total

 

 

 

 

10-14

0.007

0.012

0.014

0.011

15-19

0.112

0.144

0.163

0.136

20-24

0.245

0.257

0.277

0.256

25-29

0.284

0.273

0.293

0.282

30-34

0.270

0.237

0.263

0.258

35-39

0.209

0.149

0.197

0.184

40-44

0.107

0.079

0.091

0.093

45-49

0.029

0.030

0.032

0.030

50-54

0.009

0.014

0.013

0.011

Urban

 

 

 

 

10-14

0.003

0.003

0.002

0.003

15-19

0.071

0.084

0.074

0.072

20-24

0.230

0.237

0.208

0.230

25-29

0.277

0.226

0.208

0.272

30-34

0.269

0.209

0.220

0.264

35-39

0.217

0.131

0.216

0.212

40-44

0.106

0.042

0.099

0.101

45-49

0.023

0.023

0.032

0.024

50-54

0.008

0.000

0.017

0.008

Rural

 

 

 

 

10-14

0.013

0.013

0.015

0.014

15-19

0.167

0.146

0.168

0.158

20-24

0.268

0.258

0.281

0.268

25-29

0.292

0.275

0.297

0.286

30-34

0.272

0.238

0.264

0.255

35-39

0.199

0.150

0.196

0.176

40-44

0.109

0.080

0.090

0.090

45-49

0.034

0.030

0.032

0.032

50-54

0.009

0.014

0.012

0.012

Suggested Citation:"Appendix B: Correcting the Fertility Estimates in the 1988 Census." National Research Council. 1995. Population Dynamics of Senegal. Washington, DC: The National Academies Press. doi: 10.17226/4900.
×

TABLE B-9 Age-Specific Fertility Rates, Tambacounda, 1988 Census

 

Department

Age Group

Bakel

Kédougou

Tambacounda

Region

Total

 

 

 

 

10-14

0.023

0.014

0.025

0.022

15-19

0.202

0.197

0.229

0.215

20-24

0.278

0.252

0.296

0.282

25-29

0.260

0.226

0.275

0.261

30-34

0.230

0.149

0.234

0.215

35-39

0.151

0.108

0.125

0.129

40-44

0.071

0.044

0.055

0.058

45-49

0.031

0.015

0.027

0.026

50-54

0.015

0.012

0.014

0.014

Urban

 

 

 

 

10-14

0.002

0.003

0.010

0.008

15-19

0.144

0.139

0.154

0.151

20-24

0.264

0.241

0.283

0.273

25-29

0.240

0.254

0.302

0.287

30-34

0.300

0.174

0.285

0.267

35-39

0.141

0.131

0.150

0.145

40-44

0.084

0.076

0.071

0.075

45-49

0.020

0.015

0.016

0.017

50-54

0.000

0.009

0.020

0.014

Rural

 

 

 

 

10-14

0.024

0.017

0.029

0.025

15-19

0.206

0.207

0.248

0.226

20-24

0.279

0.254

0.300

0.284

25-29

0.261

0.222

0.269

0.257

30-34

0.224

0.145

0.219

0.205

35-39

0.152

0.104

0.119

0.127

40-44

0.069

0.036

0.050

0.054

45-49

0.032

0.015

0.030

0.027

50-54

0.016

0.013

0.012

0.014

Suggested Citation:"Appendix B: Correcting the Fertility Estimates in the 1988 Census." National Research Council. 1995. Population Dynamics of Senegal. Washington, DC: The National Academies Press. doi: 10.17226/4900.
×

TABLE B-10 Age-Specific Fertility Rates, Thiès, 1988 Census

 

Department

Age Group

Mbour

Thiès

Tivaouane

Region

Total

 

 

 

 

10-14

0.008

0.007

0.009

0.008

15-19

0.123

0.097

0.141

0.118

20-24

0.287

0.235

0.274

0.261

25-29

0.308

0.279

0.288

0.290

30-34

0.285

0.264

0.261

0.269

35-39

0.199

0.195

0.163

0.186

40-44

0.099

0.095

0.078

0.091

45-49

0.031

0.024

0.027

0.027

50-54

0.009

0.009

0.011

0.010

Urban

 

 

 

 

10-14

0.006

0.003

0.004

0.004

15-19

0.086

0.062

0.061

0.069

20-24

0.247

0.195

0.214

0.212

25-29

0.289

0.245

0.253

0.260

30-34

0.271

0.249

0.271

0.259

35-39

0.199

0.187

0.188

0.191

40-44

0.092

0.093

0.076

0.091

45-49

0.030

0.023

0.025

0.026

50-54

0.008

0.007

0.012

0.008

Rural

 

 

 

 

10-14

0.009

0.011

0.011

0.010

15-19

0.148

0.148

0.156

0.152

20-24

0.311

0.288

0.284

0.293

25-29

0.319

0.314

0.293

0.306

30-34

0.292

0.281

0.259

0.275

35-39

0.198

0.202

0.159

0.183

40-44

0.102

0.098

0.078

0.091

45-49

0.031

0.025

0.028

0.028

50-54

0.009

0.012

0.011

0.011

Suggested Citation:"Appendix B: Correcting the Fertility Estimates in the 1988 Census." National Research Council. 1995. Population Dynamics of Senegal. Washington, DC: The National Academies Press. doi: 10.17226/4900.
×

TABLE B-11 Age-Specific Fertility Rates, Ziguinchor, 1988 Census

 

Department

Age Group

Bignona

Oussouye

Ziguinchor

Region

Total

 

 

 

 

10-14

0.010

0.008

0.008

0.009

15-19

0.183

0.157

0.128

0.152

20-24

0.328

0.355

0.270

0.300

25-29

0.307

0.354

0.309

0.312

30-34

0.286

0.288

0.269

0.278

35-39

0.185

0.221

0.185

0.188

40-44

0.104

0.101

0.080

0.093

45-49

0.042

0.040

0.032

0.038

50-54

0.022

0.011

0.014

0.018

Urban

 

 

 

 

10-14

0.005

0.004

0.007

0.007

15-19

0.108

0.058

0.117

0.109

20-24

0.245

0.403

0.261

0.249

25-29

0.247

0.307

0.302

0.281

30-34

0.211

0.237

0.269

0.248

35-39

0.148

0.184

0.187

0.172

40-44

0.083

0.039

0.067

0.066

45-49

0.026

0.000

0.031

0.028

50-54

0.007

0.000

0.012

0.010

Rural

 

 

 

 

10-14

0.011

0.009

0.012

0.011

15-19

0.200

0.180

0.197

0.198

20-24

0.343

0.347

0.351

0.346

25-29

0.316

0.361

0.372

0.335

30-34

0.299

0.295

0.308

0.301

35-39

0.190

0.225

0.204

0.198

40-44

0.107

0.107

0.121

0.110

45-49

0.044

0.044

0.038

0.042

50-54

0.023

0.012

0.018

0.021

Suggested Citation:"Appendix B: Correcting the Fertility Estimates in the 1988 Census." National Research Council. 1995. Population Dynamics of Senegal. Washington, DC: The National Academies Press. doi: 10.17226/4900.
×
Page 208
Suggested Citation:"Appendix B: Correcting the Fertility Estimates in the 1988 Census." National Research Council. 1995. Population Dynamics of Senegal. Washington, DC: The National Academies Press. doi: 10.17226/4900.
×
Page 209
Suggested Citation:"Appendix B: Correcting the Fertility Estimates in the 1988 Census." National Research Council. 1995. Population Dynamics of Senegal. Washington, DC: The National Academies Press. doi: 10.17226/4900.
×
Page 210
Suggested Citation:"Appendix B: Correcting the Fertility Estimates in the 1988 Census." National Research Council. 1995. Population Dynamics of Senegal. Washington, DC: The National Academies Press. doi: 10.17226/4900.
×
Page 211
Suggested Citation:"Appendix B: Correcting the Fertility Estimates in the 1988 Census." National Research Council. 1995. Population Dynamics of Senegal. Washington, DC: The National Academies Press. doi: 10.17226/4900.
×
Page 212
Suggested Citation:"Appendix B: Correcting the Fertility Estimates in the 1988 Census." National Research Council. 1995. Population Dynamics of Senegal. Washington, DC: The National Academies Press. doi: 10.17226/4900.
×
Page 213
Suggested Citation:"Appendix B: Correcting the Fertility Estimates in the 1988 Census." National Research Council. 1995. Population Dynamics of Senegal. Washington, DC: The National Academies Press. doi: 10.17226/4900.
×
Page 214
Suggested Citation:"Appendix B: Correcting the Fertility Estimates in the 1988 Census." National Research Council. 1995. Population Dynamics of Senegal. Washington, DC: The National Academies Press. doi: 10.17226/4900.
×
Page 215
Suggested Citation:"Appendix B: Correcting the Fertility Estimates in the 1988 Census." National Research Council. 1995. Population Dynamics of Senegal. Washington, DC: The National Academies Press. doi: 10.17226/4900.
×
Page 216
Suggested Citation:"Appendix B: Correcting the Fertility Estimates in the 1988 Census." National Research Council. 1995. Population Dynamics of Senegal. Washington, DC: The National Academies Press. doi: 10.17226/4900.
×
Page 217
Suggested Citation:"Appendix B: Correcting the Fertility Estimates in the 1988 Census." National Research Council. 1995. Population Dynamics of Senegal. Washington, DC: The National Academies Press. doi: 10.17226/4900.
×
Page 218
Suggested Citation:"Appendix B: Correcting the Fertility Estimates in the 1988 Census." National Research Council. 1995. Population Dynamics of Senegal. Washington, DC: The National Academies Press. doi: 10.17226/4900.
×
Page 219
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This volume, the last in the series Population Dynamics of Sub-Saharan Africa, examines key demographic changes in Senegal over the past several decades. It analyzes the changes in fertility and their causes, with comparisons to other sub-Saharan countries. It also analyzes the causes and patterns of declines in mortality, focusing particularly on rural and urban differences.

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