We were inconsistent on this one. I consider it particularly useful when
a method starts with a `return` statement.
In other cases, we probably shouldn't have a guard rule in the middle of
a method in any case, but that's a different refactoring.
Supports controller now fill the holes in the results: When there are no
supports collected for one interval it takes the accumulated value from the
previous one.
Data starts in the publication date.
