text: #standardSQL
  # 09_05b: % of sites using ARIA role
  SELECT
    client,
    COUNT(0) AS total_sites,
    COUNTIF(uses_roles) AS total_using_roles,
    ROUND(COUNTIF(uses_roles) * 100 / COUNT(0), 2) AS perc_using_roles
  FROM (
    SELECT
      client,
      REGEXP_CONTAINS(body, r'role=[\'"]?([\w-]+)') AS uses_roles
    FROM
      `httparchive.almanac.summary_response_bodies`
    WHERE
      date = '2019-07-01' AND
      firstHtml
  )
  GROUP BY
    client
  