broker downgrade explains fall today?

Researching today for possible buy-in, found this posting below, may explain dis-proportionate drop today?
- will watch & see movements through rest of week.

Credit Suisse rates (PNA.AX PANAUST28 October,2009
PNA.AX , 0.475, +0, +0%) as Downgrade to Underperform from Neutral - The broker notes that September quarter production leaves the company in a position to deliver on its FY forecasts, as it had been assuming higher production in the December quarter anyway. However, costs in the September quarter increased significantly. As such, the broker switches over to management's guidance, which sees its FY09 EPS forecasts fall by 45%. The broker also notes that recent share price strength is enough reason to see it downgrade its recommendation to Underperform from Neutral. The price target, however, stays at 50c.

http://money.ninemsn.com.au/article.aspx?id=920652