| Year | ΔE | ΔU | DI | Degree of Decoupling |
|---|---|---|---|---|
| 2001 | -0.02 | 0.01 | -0.35 | Strong decoupling |
| 2002 | 0.00 | 0.01 | -0.06 | Weak decoupling |
| 2003 | 0.00 | 0.01 | -0.02 | Weak decoupling |
| 2004 | -0.02 | 0.01 | -0.44 | Strong decoupling |
| 2005 | 0.02 | 0.01 | 0.38 | Weak decoupling |
| 2006 | 0.00 | 0.02 | -0.06 | Weak decoupling |
| 2007 | 0.00 | 0.02 | -0.05 | Weak decoupling |
| 2008 | -0.01 | 0.02 | -0.09 | Strong decoupling |
| 2009 | 0.00 | 0.02 | -0.04 | Weak decoupling |
| 2010 | -0.02 | 0.03 | -0.23 | Strong decoupling |
| 2011 | 0.00 | 0.03 | 0.03 | Weak decoupling |
| 2012 | -0.01 | 0.04 | -0.08 | Strong decoupling |
| 2013 | -0.03 | 0.04 | -0.39 | Strong decoupling |
| 2014 | -0.04 | 0.04 | -0.69 | Strong decoupling |
| 2015 | 0.05 | 0.04 | 0.86 | Expanding connection |
