If it's a tournament during 2010, those results are unofficial. Ratings are calculated separately based on the scores in each round for unofficial ratings so they will vary. When we get the tournament report and process them officially, all rounds played on the same layout will end up with the same rating for the same score. It surprises me the people expect ratings to be the same from round to round because course conditions (and thus its difficulty) are always somewhat different even if the changes are subtle and the wind is "identical." For example, the lighting (sun position, clouds) on the course is automatically different which can make some holes more or less difficult than in the morning round. Sticks and stones on the ground are in different positions, the grass has grown, dew has dried, etc.
Rater of the tossed arc.