|of which recycled||kt||434||402||363||428||427|
|Proportion of hazardous waste to overall volume||kt||35||26||76||19||21|
|of which recycled||kt||232||219||220||272||277|
|Proportion of hazardous waste to overall volume||kt||26||24||26||32||27|
Variations in the overall waste volume produced by the Steel Division in the years from 2007 through 2011 largely reflect production output over the same period. A number of process improvements in the Tubes Division have also had a positive effect on the amount of waste from 2009 onward.