Where are the mid-sized office users in Waterloo?

Users between 5,000 and 12,000 square feet are conspicuously absent from the Waterloo office market. I just finished running a survey and I compared it to an identical search from November 2009. Of the eight options in this size range, all but one was still available from November with 3 new options. For a market with as low a vacancy rate as Waterloo, this is an interesting enigma.