Are Maths Teachers Sicker Than Teachers of Other Subjects?

It seems to me that maths teachers are sick more often than teachers of other subjects. Often I hear of maths teachers taking a week or a month or even a year off work and being taught from a book by a teacher whose specialist subject is not maths. This wouldn’t happen in geography, with so many geography teachers terrified to take a sickie, with so many geography graduates looking for a job.