I thought I knew exactly how the rankings worked, but apparently I don't. I thought they took off points for a tournament from the previous year and replaced them with the points from that tournament in the previous year the Monday after that tournament is completed. But it seems I am wrong as Federer's total points dropped on this Monday's rankings from last Monday's rankings even though he went to the finals in Rome rather than not playing last year. The only explanation I can think of is that they added his points for the final of Rome this year, but dropped the results for Hamburg last year. Is this how they do it? If it is, I don't think it makes much sense. Rankings should be based on the last 52 weeks, not the last 51.