Calculate the number of international students of University of Wisconsin-Madison in 2013.
international students refers to DIVIDE(MULTIPLY(num_students, pct_international_students), 100); University of Wisconsin-Madison refers to university_name = 'University of Wisconsin-Madison'; in 2013 refers to year = 2013
SELECT CAST(T1.num_students * T1.pct_international_students AS REAL) / 100 FROM university_year AS T1 INNER JOIN university AS T2 ON T1.university_id = T2.id WHERE T1.year = 2013 AND T2.university_name = 'University of Wisconsin-Madison'
database name:db_id university
country table country Cols: id dtype integer, country name dtype text, 
ranking_system table ranking_system Cols: id dtype integer, system name dtype text, 
ranking_criteria table ranking_criteria Cols: id dtype integer, ranking system id dtype integer, criteria name dtype text, 
university table university Cols: id dtype integer, country id dtype integer, university name dtype text, 
university_ranking_year table university_ranking_year Cols: university id dtype integer, ranking criteria id dtype integer, year dtype integer, score dtype integer, 
university_year table university_year Cols: university id dtype integer, year dtype integer, number of students dtype integer, student staff ratio dtype real, pct internation student dtype integer, pct female students dtype integer, 
