Ontario auditor general Bonnie Lysyk recently released her annual report, and has once again discovered a number of instances of government waste and mismanagement. However, one issue that she has uncovered—an increase in the number of sick days taken by teachers—is an interesting example of how people change their behaviour when faced with a change in incentives.

Prior to the 2011-12 school year, Ontario teachers could bank their unused sick leave and then cash them out as a bonus upon retirement. These banked days added up (to $47,000, to be exact). This was no small expense to the taxpayer and a significant benefit for retiring teachers. So the Dalton McGuinty government ended the ability to bank sick days, in favour of a set number of days that could be taken each year on a “use it or lose it” basis.

Now, five years down the road, the AG reports that at more than 50 school boards across the province, average sick days taken has increased 29 per cent, from nine to 11.6 days per staff member.

Should we be surprised? Are teachers playing hooky? Or are they simply making a rational choice and responding to the change in policy?

More cynical observers of this trend may imagine healthy teachers calling in sick to stick it to the government in retaliation for no longer being able to bank their sick days. And, to be fair, that may be true in isolated cases. But really, we should compare the incentives in play before and after this policy change.

We have all had those days when we wake up with a bit of a cold or other ailment and ask ourselves whether or not we are truly sick enough to stay home. Our boss may be annoyed about us staying home, but our co-workers may appreciate it if we keep our germs to ourselves. When teachers were able to bank sick leave days, staying home while suffering from a mild illness could cost them $200 or more at retirement, and they may have been inclined to go to work instead.

Now that sick days are use-it-or-lose-it, it’s much more rational to take the day at home instead. There’s no bonus for going to work and suffering while potentially spreading your germs to students and co-workers.

So are teachers sicker now than they were five years ago? Probably not. Is the fact that they take more days off now than five years ago mean something untoward is happening? Also unlikely.

We should also remember that due to the nature of their jobs, teachers are in the line of fire when it comes to contracting illness from children. It’s rather telling that elementary teachers tend to take more sick days (11.3 days) than secondary teachers (9.6 days). By the time they reach high school, students are hopefully more aware of good hygiene practices and are less likely to sneeze directly into their teacher’s face.

The leave allotment also typically includes any time needed away from work for medical or dental appointments—while many of us may be able to duck out of the office for an hour to tend to such things, teachers often have to book a substitute teacher for at least half a day.

The ability to bank sick days until retirement created a liability that Ontario’s McGuinty government felt was significant enough to warrant a policy change to end the practice. The fact that the annual number of sick days taken has increased seems to be a predictable and rational response to this change in incentives. It’s up to current and future policymakers to decide whether or not this warrants another policy change in response.