I 'think' the CAA used to allow credit for reverse thrust on dry/wet runways when certifying data, prior to EU/JAR-OPS but this is a very faint memory as I have not been around that long (honestly!).
The UKCAA most certainly did with one aircraft type, the Lockheed TriStar, as I have noticed it personally in one airline's ops manual.
In addition, it is my understanding that Boeing has approved, for USFAA registered B737-800 aircraft, a similar allowance.
Those that fly this latter type under FAA rules will undoubtedly have more information.