Shares of Pune-headquartered Tulsi Tanti-led wind turbine supplier Suzlon Energy Ltd shares plunged nearly 13% to a four-and-half-year low in the afternoon deals on Monday following heavy trading volumes. Unusually higher trading was seen in the shares of Suzlon Energy Ltd on Monday as the volumes surpassed the monthly average. Shares of\u00a0Suzlon Energy Ltd were among top five most traded stocks on NSE and was among ten-biggest losers out of 'A' group of BSE on Monday. The stock of Suzlon Energy dropped as much as 12.82% to a\u00a0four-and-half-year low of Rs 8.5 on NSE while the stock crashed 12.72% to Rs 8.51 on BSE on Monday. This was the lowest level for the share price of Suzlon since November 2013. Suzlon Energy shares made a low of Rs 8.25 on 14 November 2013 on NSE.\u00a0On the trading counters, more than 5.76 crore equity shares exchanged hands on both NSE and BSE with about 5.04 crore equity shares on NSE alone. Following the huge decline in the share prices of Suzlon Energy on Monday, the company lost about Rs 490 crore in the market capitalisation. The stock of Suzlon finally settled 9.23% to Rs\u00a08.85 on NSE. As per closing price of Rs 8.83, Suzlon Energy commands a market capitalisation of Rs\u00a04,697 crore as compared to the market capitalisation of Rs\u00a05,187 crore as at the end of Friday's closing price of Rs 9.75 on BSE.\u00a0Recently on Thursday last week, Suzlon Energy shares slipped below Rs 10 levels for the first time in the calendar year 2018. Earlier last month, Indian capital market regulator SEBI (Securities and Exchange Board of India) slapped a fine of Rs 1.1 crore as the company failed to disclose price sensitive information.\u00a0"They failed to make the disclosure on more than one occasion, hence it can be said, it is repetitive in nature," SEBI's Adjudicating Officer Sahil Malik said in the order. "Securities and Exchange Board of India by an Adjudication Order dated 20 April 2018 (the "order") has imposed a monetary penalty of a total sum of Rs 1.1 crores on the company and its compliance officer for alleged non-reporting of events in the past," Suzlon Energy said in an exchange filing.