I've had a chance to review the CMHC data for the month of May 2008 and here are the numbers.
New Housing Units Started during May - 1,757 - developers are still starting lots of projects because of the big profit margins involved. Recently I heard that the net profit margin for a suburban condo project is in the 25% - 30% range. Think about that for a minute, after the developer pays for the land, labour, and materials they still make $75k to $150k per unit. Developers have a lot of room to negotiate as prices fall.
New Housing Units Completed during May - 1,696 - developers are still having trouble completing as many units as they are starting for various reasons, including labour shortages. I expect that this will change significantly by the end of the year as lots of infrastructure projects are completed, freeing up labour to complete housing units.
New Housing Units Under Construction during May - 26,316 - near record levels of construction activity. We hit the peak in March and I don't think we'll revisit that peak for 10+ years now.
Completed and Unabsorbed new units during May - 1,422 - this is up nearly 30% from May 2007 but far from the high levels witnessed during the 90s real estate bust. Look for this number to increase dramatically as more housing is completed.
Update: Prices are correlated to supply as shown in this graph. Starts drop off at the same time as prices fall. Completions begin to outstrip starts as the correction happens.