年

  1993

  1994

  1995

  1996

  1997

1月

6,085,037

5,927,088

6,410,498

5,816,718

5,843,054

2月

5,533,344

5,427,691

5,909,701

5,369,325

5,481,074

3月

5,232,728

5,300,726

5,693,720

5,048,352

5,335,550

4月

5,339,555

5,516,706

5,739,734

5,166,341

5,393,231

5月

5,764,643

5,906,027

6,061,254

5,492,714

5,704,423

6月

6,151,310

6,248,132

6,419,695

5,869,891

6,087,891

7月

6,496,755

6,628,655

6,641,015

6,233,501

6,372,309

8月

6,817,410

6,961,419

6,834,120

6,576,643

6,694,744

9月

7,139,510

7,265,525

7,142,992

6,942,603

7,032,532

10月

7,292,479

7,429,148

7,333,726

7,145,456

7,244,192

11月

7,088,220

7,331,015

7,070,062

6,888,617

7,058,164

12月

6,649,086

6,966,148

6,502,507

6,513,261

6,524,603

单位：百万立方英尺