To provide a bit of perspective on the proportion of term contract employees versus indeterminate, about 86% of the core public administration is employed on an indeterminate basis. That means about 190,000 would be indeterminate for a longer term, where they can absorb the culture and values of the public service.
I completely support the Auditor General's point that you have to look at what these people are doing. It's a question of risk assessment and targeted measures to deal with the risk they may present.