Below is the list of tables from the database along with their columns and datatype. Need to generate an accurate SQL query for the question.
Only use the columns present in the respective table. Only use the columns which are required to generate the SQL query. Only use table joins if required and not otherwise.

### Tables ###
TABLE: CREATE TABLE table_name_97 (rank INTEGER, city VARCHAR)

### Question ###
What is teh average rank of the city of mashhad, which had less than 667770 in 1976?

### Accurate SQL ###

SELECT AVG(rank) FROM table_name_97 WHERE city = "mashhad" AND 1976 < 667770