I wasn't particularly concerned with statutory versus non-statutory; I was interested in expenditures, pure and simple, and how they're changing over time at the departmental level. I think what the final number is, whether it's statutory or not, is what should be important. How that's changing over time is what should be important. The number of people employed to do that and how that's changing over time is what should be important at the end of the day. You're right to point out that there are statutory measures that just get passed, and then the supplementary estimates adjust those as need be.
Perhaps a differentiation with respect to expenditures for a program area, whether statutory or not, is important for parliamentarians voting on it, but I think the overall number is more useful for people like me.