Clearly, the A/D ratio is a signal of the market underlying strength. A consistently high A/D ratio hints at large scale participation in the markets across segments and in such cases the uptrend becomes a lot more believable and sustainable. Check the table below that captures the month wises advances and declines as well as the A/D ratio on the BSE and the NSE over the last few years.

Month

BSE

NSE

Advances

Declines

Advance/Decline Ratio

Advances

Declines

Advance/Decline Ratio

Apr-10

2,425

725

1.3

836

484

1.7

May-10

1,125

2,035

3.3

1,029

261

3.9

Jun-10

1,500

1,678

0.9

955

285

3.4

Jul-10

2,343

863

2.7

1,129

258

4.4

Aug-10

1,838

1,391

1.3

802

593

1.4

Sep-10

1,918

1,314

1.5

937

478

2.0

Oct-10

1,778

1,452

1.2

846

574

1.5

Nov-10

1,252

2,018

0.6

483

962

0.5

Dec-10

442

2,836

0.2

143

1,304

0.1

Jan-11

946

2,323

0.4

347

1,115

0.3

Feb-11

420

2,844

0.1

96

1,371

0.1

Mar-11

1,168

2,097

0.6

547

927

0.6

Apr-11

2,671

613

4.4

1,355

129

10.5

May-11

811

2,475

0.3

242

1,245

0.2

Jun-11

1,313

1,975

0.7

550

946

0.6

Jul-11

1,775

1,524

1.2

872

637

1.4

Aug-11

610

2,699

0.2

175

1,339

0.1

Sep-11

1,265

2,042

0.6

544

980

0.6

Oct-11

975

2,332

0.4

405

1,125

0.4

Nov-11

937

2,385

0.4

390

1,152

0.3

Dec-11

522

2,802

0.2

140

1,405

0.1

Jan-12

2,301

1,021

2.3

1,195

359

3.3

Feb-12

2,617

756

3.5

1,403

151

9.3

Mar-12

1,103

2,310

0.5

452

1,106

0.4

Apr-12

1,517

1,885

0.8

681

883

0.8

May-12

888

2,469

0.4

284

1,274

0.2

Jun-12

1,395

1,953

0.7

697

861

0.8

Jul-12

2,172

1,199

1.8

1,166

395

3.0

Aug-12

1,178

2,226

0.5

510

1,054

0.5

Sep-12

1,723

1,692

1.0

894

673

1.3

Oct-12

2,295

1,139

2.0

1,223

345

3.5

Nov-12

1,414

2,014

0.7

640

930

0.7

Dec-12

1,904

1,522

1.3

989

587

1.7

Jan-13

1,514

1,495

1.0

743

837

0.9

Feb-13

702

2,278

0.3

174

1,400

0.1

Mar-13

648

2,814

0.2

193

1,378

0.1

Apr-13

1,184

2,196

0.5

521

1,045

0.5

May-13

1,638

1,613

1.0

729

594

1.2

Jun-13

933

2,245

0.4

242

1,081

0.2

Jul-13

1,156

2,006

0.6

427

901

0.5

Aug-13

823

2,347

0.4

175

1,021

0.2

Sep-13

1,819

1,371

1.3

835

360

2.3

Oct-13

2,012

1,245

1.6

916

273

3.4

Nov-13

1,954

1,328

1.5

820

354

2.3

Dec-13

1,819

1,470

1.2

757

423

1.8

Jan-14

1,978

892

2.2

660

515

1.3

Feb-14

897

1,810

0.5

382

1,138

0.3

Mar-14

1,655

1,367

1.2

968

556

1.7

Apr-14

2,439

1,039

2.3

1,316

219

6.0

May-14

2,478

1,033

2.4

1,241

306

4.1

Jun-14

3,013

559

5.4

1,432

118

12.1

Jul-14

2,082

1,506

1.4

894

654

1.4

Aug-14

1,546

2,026

0.8

639

953

0.7

Sep-14

2,351

1,249

1.9

1,121

468

2.4

Oct-14

1,431

2,177

0.7

516

1,071

0.5

Nov-14

1,944

1,143

1.7

1,012

548

1.8

Dec-14

1,332

1,762

0.8

552

1,007

0.5

Jan-15

1,733

1,728

1.0

977

576

1.7

Feb-15

1,433

2,159

0.7

593

913

0.6

Mar-15

1,112

2,487

0.5

593

1,042

0.6

Apr-15

1,926

1,600

1.2

898

625

1.4

May-15

1,226

2,267

0.5

402

1,114

0.4

Jun-15

1,102

2,387

0.5

404

1,113

0.4

Jul-15

2,425

1,105

2.2

1,210

310

3.9

Aug-15

1,867

1,738

1.1

773

751

1.0

Sep-15

730

2,755

0.3

201

1,335

0.2

Oct-15

2,473

1,020

2.4

1,278

258

5.0

Nov-15

1,674

1,808

0.9

662

882

0.8

Dec-15

2,313

1,147

2.0

1,068

476

2.2

Jan-16

2,417

810

3.0

565

994

0.6

Feb-16

553

2,652

0.2

140

1,432

0.1

Mar-16

1,492

1,928

0.8

859

713

1.2

Apr-16

2,290

1,074

2.1

1,248

336

3.7

May-16

1,682

1,688

1.0

802

777

1.0

Jun-16

1,714

1,712

1.0

943

644

1.5

Jul-16

2,524

929

2.7

1,341

253

5.3

Aug-16

1,608

1,883

0.9

726

883

0.8

Sep-16

1,901

1,604

1.2

907

709

1.3

Oct-16

2,370

1,198

2.0

1,093

532

2.1

Nov-16

1,289

2,271

0.6

313

1,325

0.2

Dec-16

1,333

2,162

0.6

530

1,109

0.5

Jan-17

2,139

1,149

1.9

1,328

317

4.2

Feb-17

2,195

1,129

1.9

1,078

590

1.8

Mar-17

1,629

1,973

0.8

819

861

1.0

Apr-17

2,511

1,077

2.3

1,327

351

3.8

May-17

1,616

1,941

0.8

766

931

0.8

Jun-17

1,310

2,171

0.6

668

1,022

0.7

Jul-17

2,005

1,411

1.4

1,060

634

1.7

Aug-17

995

2,401

0.4

484

1,237

0.4

Sep-17

1,835

1,500

1.2

1,060

660

1.6

Oct-17

1,871

1,508

1.2

986

741

1.3

Nov-17

2,120

1,337

1.6

1,179

576

2.0

Dec-17

2,058

1,371

1.5

1,089

685

1.6

Jan-18

2,505

813

3.1

1,357

444

3.1

Feb-18

924

2,393

0.4

237

1,587

0.1

Mar-18

723

2,750

0.3

269

1,560

0.2

Apr-18

1,982

1,449

1.4

1,180

659

1.8

May-18

992

2,448

0.4

486

1,378

0.4

Jun-18

779

2,651

0.3

361

1,517

0.2

Jul-18

842

2,579

0.3

415

1,478

0.3

Aug-18

2,080

1,415

1.5

1,254

637

2.0

Sep-18

1,174

2,331

0.5

532

1,361

0.4

Oct-18

481

2,973

0.2

159

1,741

0.1

Nov-18

1,984

1,457

1.4

1,210

697

1.7

Dec-18

1,314

2,095

0.6

741

1,169

0.6

As can be seen from the above table, the best way is to juxtapose the above trends with the index movement and you can get clear trends about the sustainability of the trend.