| # of obs. | percentage |
2010 | 1514 | 13.02% |
2011 | 1563 | 13.44% |
2012 | 1721 | 14.80% |
2013 | 2055 | 17.67% |
2014 | 2320 | 19.95% |
2015 | 2454 | 21.11% |
Total firm-year observations: | 11,627 | 100% |