Industrially backward districts designation establishes Category A and B for section 80-IB applicability from specified assessment year. The Central Government, under sub-section (5) of section 80-IB and rule 11EA, designates specified districts as industrially backward and classifies them into Category A and Category B by superseding the earlier notification; the designation follows the Study Group report and the 1991 census, and where a district has been reorganised after that census, all areas that comprised the district as it existed in the 1991 census qualify; the notification applies from the previous year relevant to the assessment year commencing on the first day of April, 2000 and subsequent assessment years.