Notable Analyst Rating Changes 12/19: (POT) (CVS) (AV) Upgraded; (PWE) (WAIR) (SDRL) Downgraded - InvestingChannel

Notable Analyst Rating Changes 12/19: (POT) (CVS) (AV) Upgraded; (PWE) (WAIR) (SDRL) Downgraded

UPGRADES
UBS upgrades Potash Corp. (NYSE: POT) from Neutral to Buy and moves its price target from $30 to $40. Click Here for more color.

SunTrust Robinson Humphrey raises CVS Caremark (NYSE: CVS) from Neutral to Buy with a price target of $110.

Bernstein boosts Aviva plc (NYSE: AV) from Market Perform to Outperform.

KeyBanc moves Medical Properties Trust (NYSE: MPW) from Underweight to Hold. Click Here for more color.

For daily real-time Upgrades go to http://www.streetinsider.com/Upgrades

DOWNGRADES
TD Securities trims Penn West Energy (NYSE: PWE) from Hold to Reduce with a price target