ASI

Asset Stewardship Index. This was developed by ORR and introduced in April 2004 after the Access Charges Review 2003. The ASI is a composite measure comprising track geometry, broken rails, Level 2 exceedences, points/track circuit failures, signalling failures, electrification failures and structures/earthworks related TSRs.  The index is based on a ceiling level of 1.1 to be reached at 2008/9.  It is calculated such that the lower the current index is, the better.