| December 1997 |
3,447,600 |
| November 1997 |
3,463,700 |
| October 1997 |
3,486,300 |
| September 1997 |
3,507,400 |
| August 1997 |
3,479,400 |
| July 1997 |
3,429,200 |
| June 1997 |
3,368,800 |
| May 1997 |
3,240,100 |
| April 1997 |
3,109,000 |
| March 1997 |
2,880,600 |
| February 1997 |
2,588,600 |
| January 1997 |
2,400,100 |
|
