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_51323 ( "Episode" text, "Air Date" text, "Timeslot (EST)" text, "Season" real, "Rating" real, "Share" real, "18\u201349" real, "Viewers (m)" real, "Rank (#)" text )

### Question ###
What is the total number of ratings among the 18 to 49 group that was aired on January 7, 2009?

### Accurate SQL ###

SELECT COUNT("18\u201349") FROM table_51323 WHERE "Air Date" = 'january 7, 2009'