If you want to check repetition more than 1 in descending order then implement below query.
SELECT duplicate_data,COUNT(duplicate_data) AS duplicate_data
FROM duplicate_data_table_name
GROUP BY duplicate_data
HAVING COUNT(duplicate_data) > 1
ORDER BY COUNT(duplicate_data) DESC
If want simple count query.
SELECT COUNT(duplicate_data) AS duplicate_data
FROM duplicate_data_table_name
GROUP BY duplicate_data
ORDER BY COUNT(duplicate_data) DESC