Parliament cannot exceed the appropriation level that is approved by Parliament. Having some lapse is normal in the operation because managers have to ensure that they're not going to exceed that, so they are obviously very prudent in managing their finances. Normally what happens is that at the end of the year some money is left over, but in the past few years we have seen a significant increase in the amount of lapse.
On April 29th, 2014. See this statement in context.