Why is eclerx showing a sharp fall on Dec 17?

I see that eclerx share price has fallen sharply on Dec 17. Why is it so? Can someone explain?

http://www.nseindia.com/charts/webtame/webchart.jsp?CDSymbol=ECLERX&Segment=CM&Series=EQ&CDExpiryMonth=&FOExpiryMonth=&IRFExpiryMonth=&CDDate1=&CDDate2=&PeriodType=1&Periodicity=1&Template=tame_Historical_Quarterly.jsp

Is it due to the issue of bonus shares? If yes, when will i get the shares in my account?

Yes, the stock went ex-bonus on 17th Dec. You should have got it by now.