Table:
text: List of public sector undertakings in India
Transport
Transport
S_No Company Incorporated Ministry Sector
1 Air India Air Transport Services Ltd. 2003 Ministry Of Civil Aviation Services
2 Air India Charters 1972 Ministry Of Civil Aviation Services
3 Air India Engineering Services Ltd. 2006 Ministry Of Civil Aviation Enterprises Under Construction
4 Airline Allied Services Ltd. 1983 Ministry of Civil Aviation Services
5 Airports Authority Of India Ltd. 1996 Ministry of Civil Aviation Services

Question: What is the sector of the company with incorporation date before 1983 in the list of public sector companies in India?

Question: What is the average year of incorporation of Air India Charters company in the list of public sector companies in India?