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_20041 ( "Season" real, "# of Episodes" real, "Timeslot" text, "Season Premiere" text, "Season Final" text, "Peak Audience" real, "Average Audience" real, "Average Nightly Rank" text, "Average Weekly Rank" text, "Average Yearly Ranking" text )

### Question ###
How many were the show's average weekly ranking when it reached No. 2 in average nightly ranking?

### Accurate SQL ###

SELECT COUNT("Average Weekly Rank") FROM table_20041 WHERE "Average Nightly Rank" = 'No. 2'