#standardSQL
SELECT
  COUNT(*) AS num_downloads,
  DATE_TRUNC(DATE(timestamp), DAY) AS `day`
FROM `bigquery-public-data.pypi.file_downloads`
WHERE
  file.project = '<PROJECT_NAME>'
  AND DATE(timestamp)
    BETWEEN DATE_TRUNC(DATE_SUB(CURRENT_DATE(), INTERVAL 18 MONTH), MONTH)
    AND CURRENT_DATE()
GROUP BY `day`
ORDER BY `day` DESC