The hours are not able to be retrieved until the DESS models came out in 95. I see between 100 and 200 a lot on the old 2-seaters. Larger and newer skis generally have another hundred hours on them on top of that.
This number will vary to a LARGE degree based on location and the person owning the ski(s). A FL ski can easily get 100 hours a year. A northern ski may get as little as 10 hours a year.