| Year | ISO index WCA | ISO index ECA | ENSO index |
| 1997 | 0.18 | −0.14 | 1.92 |
| 1998 | −0.63 | −0.75 | 0.17 |
| 1999 | −1.53 | 0.65 | −1.60 |
| 2000 | −0.22 | 0.15 | −1.30 |
| 2001 | 0.65 | 1.75 | −0.28 |
| 2002 | 0.07 | −0.8 | 1.20 |
| 2003 | −1.6 | −0.21 | 0.47 |
| 2004 | 0.09 | 2.05 | 0.68 |
| 2005 | −1.51 | −0.6 | 0.16 |
| 2006 | 0.92 | −0.1 | 0.23 |
| 2007 | 1.81 | −0.08 | −0.71 |
| 2008 | 0.11 | 0.63 | −0.99 |