In World Cup event, tasks can be scored on 1000 points or less in case the task validation distance was not reached by at least 20 pilots.
So we have two kind of tasks, the one scored on 1000 points, and the others.
Up to 2006, only the results made by pilots in the 1000 points tasks were used to compute the World Cup rankings.
In 2007 the World Cup committee introduced the possibility to use a good result in a non 1000 points task in the overall world cup ranking. The overall ranking now shows the non 1000 points tasks for this reason. In the past, these tasks were not displayed at all on the overall ranking.
The discard system is still the same: 1 discard every 3 "1000 point task".

For example, after task 23, we had 22 tasks scored on 1000 points, so there is 7 discards and we score the overall ranking on 22-7 = 15 bests tasks.
The total number of tasks is 23, so in the overall ranking listings 8 columns are striked-thru to keep only the 15 best ones for each pilot.