Today, for my edification and perhaps somebody else's, I've produced this graph of single-family home sales (ignore the incorrect labels).
Again I've plotted the data as sales per 1,000 population. Unlike the starts data (which is for all units) the trend is up - though the bubble probably made the slope steeper. I don't know what has caused the uptrend, so I'll speculate: this data shows sales, and the increase reflects people buying more spec homes and ordering less custom homes. Sounds plausible. I'll try to figure out what is really going on next month.
Another thing to note is that while the YoY declines have only briefly exceeded 50%, the decline from the peak is currently at 76%. That is a stunning number.