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According to the records kept by the Treasury Solicitor's Department, the average time spent when instructed in Asylum and Immigration Tribunal appeals for the financial year 2006-07 was 21.6 hours per case. The Treasury Solicitor's Department does not keep records that differentiate between the time spent on different types of appeals heard before the Asylum and Immigration Tribunal and therefore cannot state the average time spent on each of the categories of appeal set out in the question.