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_47 ( inception VARCHAR, assets_us$billion VARCHAR, abbreviation VARCHAR )

### Question ###
What's the inception for the country with 25.5 billion USD in assets and an abbreviation of psf?

### Accurate SQL ###

SELECT inception FROM table_name_47 WHERE assets_us$billion = "25.5" AND abbreviation = "psf"