Month

Number of

observations

Mean

Max

Min

ADF

(t-statistics)

GPH

(d value)

GSP

(d value)

Jan.

960

517213

2617444

109180

−10.4575^*

0.5885

0.5332

Feb.

720

578184

2032704

132651

−4.9658^*

0.5653

0.5490

Mar.

1104

597276

2921257

134438

−8.7126^*

0.5403

0.5735

Apr.

912

604845

3010937

175328

−8.6219^*

0.5591

0.5880

May.

1008

315125

1052178

98968

−7.7034^*

0.4277

0.4303

Jun.

1008

349801

1515968

85317

−6.6711^*

0.4829

0.4470

Jul.

1008

412374

2153114

96716

−10.6532^*

0.4949

0.5078

Aug.

1104

361702

2835370

83057

−9.1132^*

0.5173

0.5241

Sep.

1008

269615

1563451

63966

−10.6051^*

0.4033

0.4006

Oct.

768

386268

2983349

70697

−9.0214^*

0.5066

0.4673

Nov.

1056

297883

1356324

66211

−6.5933^*

0.5083

0.5431

Dec.

1056

247512

4117696

60367

−10.3629^*

0.4056

0.4242

Average

-

-

-

-

-

0.5000

0.4990