Delete votes are hard to come by so take care not to waste them on stuff that will be automagically deleted.
There are currently ~1700 questions that are closed and have no answersclosed and have no answers. If they are older than a month then chucking downvotes at them so they reach -1 is the best solution.
There are >5000 Closed questions that have answers, the back of the listthe back of the list would be a good place to start casting delete votes. Please though, pay attention to the view counts, some older questions that are now not favoured are great crowd pullersgreat crowd pullers.
The rules for automagic deletion
If the question is more than 30
days old, and ...
- has -1 or lower score
- has no answers
- is not locked
... it will be automatically deleted.
If the question is more than 365
days old, and ...
- has a score of 0 or a score of 1 with a deleted owner
- has no answers
- is not locked
- has a viewcount <= the age of the question in days times 1.5
- has 1 or 0 comments
... it will be automatically deleted