Shares of MindTree Ltd plunged as much as 18.1 per cent at 801.1 rupees on a cautious macro outlook particularly in the UK market.The IT firm's stock marks biggest intraday per cent loss since Sept 2011.Sept-quarter profit surged about 65 per cent to 2.06 billion rupees ($13.61 million), co said on Wednesday.Macquarie Research cuts stock's price target to 920 rupees from 940 rupees; maintains "underperform" rating.Goldman Sachs cuts PT to 1,394 rupees from 1,455 rupees; maintains "buy" rating.Modestly cut FY2019-FY2021 earnings per share estimates to account for weaker-than-expected topline growth in Q2 and cautious growth outlook shared by management in the near term in the UK market because of Brexit - Goldman Sachs.Quarter revenues missed estimate and surprised negatively; management cautioned on macro volatility leading to delays in closure of some deals - Morgan Stanley.About 5 million shares change hands, 3.4 times their 30-day moving avg of 1.4 million shares.Up to last close, stock up 60 per cent this year ($1 = 73.4700 Indian rupees)