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_204_163 ( id number, "airline" text, "icao" text, "iata" text, "callsign" text, "commenced\noperations" number )

### Question ###
how many years after uganda air cargo commenced operations did air uganda commence operations ?

### Accurate SQL ###

SELECT (SELECT "commenced\noperations" FROM table_204_163 WHERE "airline" = 'air uganda') - (SELECT "commenced\noperations" FROM table_204_163 WHERE "airline" = 'uganda air cargo')