We're speaking strictly about reading and writing, but what we found about literacy is that in fact you can lose literacy skills; someone who actually has a grade 12 diploma but is involved in a job like long-distance trucking and isn't using his literacy skills could actually lose those skills over time. If they lose that job, then they find that they have to upgrade to get another job that has a higher level of literacy. Literacy is a flexible and mobile thing; it's something you have to keep up and keep using.
On October 17th, 2006. See this statement in context.