Why is Pro Stock Dodge down on horsepower ?

ok..it was Billy....Bob did not make the six second club...

1. Kurt Johnson May 20, 1994 6.988 Englishtown, N.J.
2. Darrell Alderman Aug. 5, 1994 6.994 Seattle
3. Warren Johnson March 10, 1995 6.981 Houston
4. Bill Glidden March 12, 1995 6.999 Houston
So Kurt and Warren used NOS too?