Please read the following table in Markdown format and then answer the question according to the table. Table cells in one row are seperated by '|', and different rows are seperated by '
'.

Table:
| S.No | Company | Incorporated | Ministry | Sector |
| --- | --- | --- | --- | --- |
| 1.0 | Air India Air Transport Services Ltd. | 2003.0 | Ministry Of Civil Aviation | Services |
| 2.0 | Air India Charters | 1972.0 | Ministry Of Civil Aviation | Services |
| 3.0 | Air India Engineering Services Ltd. | 2006.0 | Ministry Of Civil Aviation | Enterprises Under Construction |
| 4.0 | Airline Allied Services Ltd. | 1983.0 | Ministry of Civil Aviation | Services |
| 5.0 | Airports Authority Of India Ltd. | 1996.0 | Ministry of Civil Aviation | Services |
Question:
What is the sector of the company with an incorporated date before 1983?
Answer:
Services