BUZZ-Bunzl: Credit Suisse downgrades to "underperform"
** Business supplies distributor Bunzl Plc's shares down ~1% after Credit Suisse downgrades to "underperform" from "neutral"
** CS says combination of limited organic growth and falling underlying margins more than offsets the on-going opportunity to grow the business via M&A
** Says revenue growth and margins will be further constrained through 2019 by weakness in product input costs
** Co warned of slowing growth, particularly in its biggest market North America and said rate of underlying revenue growth had slowed during Q1 in April
** CS sees potential pressure on volumes for co's existing key clients, which will in turn put further pressure on pricing discussions
** CS forecasts EPS estimates to fall 3-6% for 2019 to 2021, also cuts PT to 2100p from 2450p (Reporting By Geetha Panchaksharam)