** Next falls 2 pct on Credit Suisse rating cut
** Credit Suisse slashes co rating to underperform fromneutral
** Stock top loser on FTSE-100 Index
** CS cites citing rising concerns from gradual slowdown inco's near and medium term growth drivers
** More than one-fifth of 30-day average volume traded inthe first half of market open
** 5 of 27 brokerages rate the stock "buy" or higher, 19"hold" and 3 "sell" or lower
** Up to Thursday's close, stock had risen 19 pct (aashika.jain@thomsonreuters.com)