And this compares to the followong market value development.
The two curves are strikingly similar. The Goalimpact rises until February 2007 where it reaches a plateau at 124. The market value also shows an increase until April 2004 when a plateau starts. In October 2007 the Goalimpact starts dropping until it reaches a bottom in March 2008. The market value drops, too. Putting the bottom at July 2008.
The Goalimpact rises again until it reaches another plateau from March 2009 until October 2010. We see again the same pattern in the market value where the plateau lasts from February 2009 until Februrary 2011. Both start raising thereafter again. Goalimpact peaks in February 2011 and drops slightly January 2012. The market value peaks August 2011 and drops slightly February 2012.
Until then, the two values move in parallel to an amazing extend. If you check the date, you will see that the Goalimpact usually reacts about three month earlier.
However, in 2012 the two curve move differently. The market value dropped significantly while the Goalimpact is more or less unchanged. If Hamburg SV could buy him at these low prices, that would be a good deal.