| 1999-2007 | 1999-2008 | 2009-2013 | 1999-2013 | ||||
| Coeff. | t | Coeff. | t | Coeff. | t | Coeff. | t |
k | −0.133 | −3.426 | −0.100 | −2.542 | 0.263 | 12.265 | 0.146 | 7.896 |
| 0.351 | 29.741 | 0.341 | 29.425 | 0.138 | 4.836 | 0.271 | 41.114 |
| 0.111 | 4.620 | 0.096 | 5.300 | 0.145 | 5.316 | 0.131 | 7.903 |
| −0.242 | −6.388 | −0.250 | −7.132 | −0.235 | −6.707 | −0.144 | −5.721 |
long | 0.893 | 0.880 | 0.287 | 0.905 | ||||
short | 0.437 | 0.480 | 0.822 | 0.444 |