SELECT
  school_year,
  ABS(
    (
      (
        SUM(
          CASE
            WHEN student_subgroup = 'BLACK_OR_AFRICAN_AMERICAN' THEN merged_proficient_or_above_count
            ELSE 0
          END
        ) * 100.0
      ) / (
        NULLIF(
          SUM(
            CASE
              WHEN student_subgroup = 'BLACK_OR_AFRICAN_AMERICAN' THEN student_subgroup_total_tested
              ELSE 0
            END
          ),
          0
        )
      )
    ) - (
      (
        SUM(
          CASE
            WHEN student_subgroup = 'WHITE' THEN merged_proficient_or_above_count
            ELSE 0
          END
        ) * 100.0
      ) / (
        NULLIF(
          SUM(
            CASE
              WHEN student_subgroup = 'WHITE' THEN student_subgroup_total_tested
              ELSE 0
            END
          ),
          0
        )
      )
    )
  ) AS achievement_gap
FROM
  stats_v2
WHERE
  stats_v2.data_level = 'STATE'
  AND stats_v2.student_group = 'RACE_ETH'
  AND state = 'Michigan'
  AND subject = 'MATH'
  AND (
    student_subgroup = 'BLACK_OR_AFRICAN_AMERICAN'
    OR student_subgroup = 'WHITE'
  )
  AND merged_proficient_or_above_count IS NOT NULL
  AND student_subgroup_total_tested IS NOT NULL
  AND student_subgroup_total_tested > 0
GROUP BY
  school_year
HAVING
  (
    NULLIF(
      SUM(
        CASE
          WHEN student_subgroup = 'BLACK_OR_AFRICAN_AMERICAN' THEN student_subgroup_total_tested
          ELSE 0
        END
      ),
      0
    )
  ) > 0
  AND (
    NULLIF(
      SUM(
        CASE
          WHEN student_subgroup = 'WHITE' THEN student_subgroup_total_tested
          ELSE 0
        END
      ),
      0
    )
  ) > 0