select
  round(avg(total_value)) as SA_MEDIAN
from (
  select total_value
  from convenience
  where
    survey_year = 2019 and kind_code = '100'
  order by total_value
  limit 2 - (select count(1) from convenience where survey_year = 2019 and kind_code = '100') % 2
  offset cast(((select count(1) from convenience where survey_year = 2019 and kind_code = '100')-1) / 2  as int)
);