Catch up on today's top five analyst downgrades with this list compiled by The Fly: 1. Twitter (TWTR) downgraded to Underperform from Sector Perform by RBC analyst Mark Mahaney, who cut his price target to $14 from $17. The research firm's survey of more than 1,100 advertising professionals and their attitudes towards Facebook (FB), Google (GOOG), Twitter and other high-profile names showed that, despite marketing budgets continuing to shift online, interest in the microblog platform appears to be declining. Of note, Twitter shares have surged this morning after CNBC's David Faber reported that Twitter is moving closer to selling itself and has received expressions of interest in a possible sale, although no deal is imminent. 2. Yum! Brands (YUM) downgraded to Outperform from Top Pick by RBC Capital analyst David Palmer based on valuation. His price target on Yum shares remains $97. 3. Becton Dickinson (BDX) downgraded to Sell from Neutral by Citi analyst Amit Hazan, who thinks a cyclical U.S. slowdown will push the company's organic growth below expectations. The analyst, who also sees a diminishing impact on Becton's growth from emerging markets, cut his price target for the shares to $165 from $167. 4. NextEra Energy (NEE) downgraded to Hold from Buy by Deutsche Bank analyst Jonathan Arnold, as he sees limited near-term upside with the shares up 23% year-to-date. "Extraordinarily frosty commentary" from two of three PUCT commissioners yesterday regarding NextEra's Oncor deal indicates an uphill battle in getting it approved, Arnold tells investors. 5. AVANGRID (AGR) downgraded to Underweight from Neutral by JPMorgan analyst Christopher Turnure, who thinks both the company's growth guidance and consensus expectations "appear ambitious." He lowered his price target for the shares to $41 and $44 and notes he does not have confidence in AVANGRID's near-term growth. This list is just a portion of The Fly's full analyst coverage. To see The Fly's full Street Research coverage, click here.