I had to make my own spreadsheet for this one, because GVOC changed their scoring formula this year, away from the % behind winner, which is what I was after.
In previous years:
your score = 1000 * (your time) / (winning time)
your score = 1000 * [1 - ((your time - winning time) / (winning time))]
In practice, the score dropoffs are sharper this year. This is best exemplified with someone with double the winning time. In previous years, this person would get 500 points. This year, this person gets 0!