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_37 ( silver INTEGER, rank INTEGER )

### Question ###
How many Silver medals did the Nation with a Rank of less than 1 receive?

### Accurate SQL ###

SELECT AVG(silver) FROM table_name_37 WHERE rank < 1