| 8-K | Report of unscheduled material events or corporate event | May 2, 2013 |     |
| 8-K | Report of unscheduled material events or corporate event | Apr 11, 2013 |     |
| 4 | Statement of changes in beneficial ownership of securities | Apr 4, 2013 |    |
| 4 | Statement of changes in beneficial ownership of securities | Apr 4, 2013 |    |
| 10-Q | Quarterly report which provides a continuing view of a company's financial position | Apr 3, 2013 |       |
| 8-K | Report of unscheduled material events or corporate event | Apr 3, 2013 |     |
| 8-K | Report of unscheduled material events or corporate event | Mar 22, 2013 |     |
| 4 | Statement of changes in beneficial ownership of securities | Mar 21, 2013 |    |
| 4 | Statement of changes in beneficial ownership of securities | Mar 21, 2013 |    |
| 4 | Statement of changes in beneficial ownership of securities | Mar 21, 2013 |    |
| 4 | Statement of changes in beneficial ownership of securities | Mar 21, 2013 |    |
| 4 | Statement of changes in beneficial ownership of securities | Mar 21, 2013 |    |
| 4 | Statement of changes in beneficial ownership of securities | Mar 21, 2013 |    |
| 4 | Statement of changes in beneficial ownership of securities | Mar 21, 2013 |    |
| 8-K | Report of unscheduled material events or corporate event | Mar 11, 2013 |     |
| 8-K | Report of unscheduled material events or corporate event | Feb 28, 2013 |     |
| SC 13G/A | Amendment to a previously filed SC 13G | Feb 14, 2013 |    |
| SC 13G | Schedule filed to report acquisition of beneficial ownership of 5% or more of a class of equity securities by passive investors and certain institutions | Feb 13, 2013 |     |
| SC 13G/A | Amendment to a previously filed SC 13G | Feb 11, 2013 |    |
| DEF 14A | Official notification to shareholders of matters to be brought to a vote ("Proxy") | Feb 7, 2013 |     |
| SC 13G | Schedule filed to report acquisition of beneficial ownership of 5% or more of a class of equity securities by passive investors and certain institutions | Feb 4, 2013 |    |
| 4 | Statement of changes in beneficial ownership of securities | Jan 31, 2013 |    |
| 4 | Statement of changes in beneficial ownership of securities | Jan 25, 2013 |    |
| 4 | Statement of changes in beneficial ownership of securities | Jan 25, 2013 |    |
| 4 | Statement of changes in beneficial ownership of securities | Jan 25, 2013 |    |