Here are Monday's biggest analyst calls of the day, including a risky upgrade of Carnival

Key Points
  • HSBC upgraded Carnival Cruise Line to buy from hold.
  • Stifel downgraded Lyft to hold from buy.
  • SunTrust downgraded Conagra Brands to hold from buy.
  • Citi downgraded Monster Beverage to neutral from buy.
  • BMO downgraded Yelp to market perform from outperform.
  • Morgan Stanley resumed AbbVie as overweight.
  • Susquehanna downgraded Redfin to neutral from positive.
  • Needham raised its price target on Nvidia to $360 from $270.