What is the percentage of the words that have been repeated under 180 times in the Catalan language?
repeated under 180 times refers to occurrences < 180; Catalan language refers to lang = 'ca'; DIVIDE(COUNT(words WHERE occurrences < 180 and lang = 'ca'), COUNT(words WHERE lang = 'ca')) as percentage;
SELECT CAST(COUNT(CASE WHEN T2.occurrences < 180 THEN 1 ELSE NULL END) AS REAL) * 100 / COUNT(T1.lid) FROM langs AS T1 INNER JOIN langs_words AS T2 ON T1.lid = T2.lid WHERE T1.lang = 'ca'