{"main_topic":"education","sub_topic":"school_zones","topic":"school_attendance_zone_tracts","key":"education/school_zones/school_attendance_zone_tracts","version":"1.0.0","year_min":2027,"year_max":2027,"year_gaps":[],"update_frequency":"as zones change","detail_levels":["schools"],"default_detail":"schools","path_template":"education/school_attendance_zone_tracts/year={year}/{detail}.parquet","grain":["year","district_code","school_code","grade_level","tract_geoid"],"title":"School Attendance Zone Tracts","summary":"Which 2020 census tracts each Georgia school attendance zone covers at each grade, with population and land-area shares.","description":"A crosswalk between Georgia public school attendance zones (the school_attendance_zones geometry topic: the area whose residents a school serves for a run of grades) and 2020 census tracts. One row per school, grade and tract its zone covers at that grade. Population weights are 2020 Census P.L. 94-171 block populations: each 2020 block counts toward the zone holding its interior point; a block that a zone line crosses (two or more schools' zones, or a zone and an unzoned gap, each covering over 1% of it) is split by area, in whole persons; a block whose interior point lies just outside today's district line goes to the zone covering most of it; any other block outside every zone is a gap. Use pct_of_tract_population to answer 'which zones cover this tract at this grade, and how much of it', and pct_of_zone_population to roll tract data (the census topics) up to a zone. year is the school year the zones are in effect for (2027 = 2026-27); the population is the 2020 census. Zones are not official enrollment determinations; each zone's source, method, vintage and accuracy are on the zones topic.","explorer":false,"source":"School attendance zones (this platform's school_attendance_zones topic, built from district and vendor sources); U.S. Census Bureau 2020 Census P.L. 94-171 block populations, TIGER/Line 2020 blocks and tracts, and TIGER/Line school district outlines.","source_url":"https://www.census.gov/programs-surveys/decennial-census/about/rdo/summary-files.html","endpoint":"/api/v1/education/school_attendance_zone_tracts","columns":[{"name":"year","type":"integer","role":"year","nullable":false,"label":"Year","short_description":"","description":"School year the zones are in effect for, as its ending calendar year (2027 = 2026-27). The weights are 2020 census counts.","valid_values":null,"example":2027,"unit":null,"value_min":null,"value_max":null,"null_meaning":null,"key_metric_grain_contributor":false,"metric_component":null},{"name":"district_code","type":"string","role":"fk_district","nullable":false,"label":"District Code","short_description":"","description":"GOSA district code (FK to the districts dimension).","valid_values":null,"example":"667","unit":null,"value_min":null,"value_max":null,"null_meaning":null,"key_metric_grain_contributor":false,"metric_component":null},{"name":"school_code","type":"string","role":"fk_school","nullable":false,"label":"School Code","short_description":"","description":"4-digit GOSA school code (composite FK to the schools dimension with district_code): the zone's school.","valid_values":null,"example":"0177","unit":null,"value_min":null,"value_max":null,"null_meaning":null,"key_metric_grain_contributor":false,"metric_component":null},{"name":"zone_level","type":"string","role":"categorical","nullable":false,"label":"Zone Level","short_description":"Elementary, middle or high zone.","description":"The level of the school's zone at this grade on the zones topic: elementary, middle or high. It follows from the grade and the school (a 6-8 middle school's grade 6, a K-6 school's grade 6 at elementary), so pin grade_level first.","valid_values":["elementary","high","middle"],"example":"elementary","unit":null,"value_min":null,"value_max":null,"null_meaning":null,"key_metric_grain_contributor":false,"metric_component":null},{"name":"grade_level","type":"string","role":"categorical","nullable":false,"label":"Grade Level","short_description":"Grade (k, 01-12).","description":"The grade the row's shares hold for (k, 01-12; pre-K is not zoned). A school's zone usually covers the same tracts at every grade it assigns; it differs where the zone differs by grade (a phased-in rezoning) or a neighbour exists at only some grades.","valid_values":["01","02","03","04","05","06","07","08","09","10","11","12","k"],"example":"k","unit":null,"value_min":null,"value_max":null,"null_meaning":null,"key_metric_grain_contributor":true,"metric_component":null},{"name":"tract_geoid","type":"string","role":"fk_tract","nullable":false,"label":"Tract GEOID","short_description":"","description":"11-digit 2020 census tract GEOID (FK to the tracts dimension), as used by the census topics.","valid_values":null,"example":"13121001100","unit":null,"value_min":null,"value_max":null,"null_meaning":null,"key_metric_grain_contributor":false,"metric_component":null},{"name":"num_population","type":"integer","role":"metric","nullable":true,"label":"Number Population","short_description":"","description":"2020 census population of the tract living in the zone: whole blocks by interior point, plus the zone's area-weighted part of blocks a zone line crosses (in whole persons).","valid_values":null,"example":1840,"unit":"count","value_min":null,"value_max":null,"null_meaning":null,"key_metric_grain_contributor":false,"metric_component":"numerator"},{"name":"num_tract_population","type":"integer","role":"metric","nullable":true,"label":"Number Tract Population","short_description":"","description":"The tract's 2020 census population (all of its blocks), repeated on each of its rows: never add it across rows.","valid_values":null,"example":4312,"unit":"count","value_min":null,"value_max":null,"null_meaning":null,"key_metric_grain_contributor":false,"metric_component":"denominator"},{"name":"pct_of_tract_population","type":"number","role":"metric","nullable":true,"label":"Percent of Tract Population","short_description":"Share of the tract's 2020 population living in this zone.","description":"Share of the tract's 2020 population living in this zone at this grade (num_population / num_tract_population). Across a tract's zones at one grade it adds to 1 when the tract is fully zoned.","valid_values":null,"example":0.4267,"unit":"proportion","value_min":null,"value_max":null,"null_meaning":"The tract had no 2020 census population.","key_metric_grain_contributor":false,"metric_component":null},{"name":"pct_of_tract_area","type":"number","role":"metric","nullable":true,"label":"Percent of Tract Area","short_description":"","description":"Share of the tract's 2020 land area in this zone, from the same block weights as the population.","valid_values":null,"example":0.3811,"unit":"proportion","value_min":null,"value_max":null,"null_meaning":"The tract has no land area (water only).","key_metric_grain_contributor":false,"metric_component":null},{"name":"pct_of_zone_population","type":"number","role":"metric","nullable":true,"label":"Percent of Zone Population","short_description":"","description":"Share of the zone's 2020 population at this grade living in this tract (adds to 1 over the zone's tracts at the grade). Multiply a tract count by pct_of_tract_population, or weight tract rates by this share, to roll tract data up to the zone.","valid_values":null,"example":0.2104,"unit":"proportion","value_min":null,"value_max":null,"null_meaning":"The zone had no 2020 census population.","key_metric_grain_contributor":false,"metric_component":null},{"name":"is_largest_zone_for_tract","type":"boolean","role":"categorical","nullable":true,"label":"Is Largest Zone for Tract","short_description":"","description":"True for the zone holding the most of the tract's 2020 population at this grade (ties go to more land area, then the lower district and school code): exactly one row per tract and grade.","valid_values":null,"example":true,"unit":null,"value_min":null,"value_max":null,"null_meaning":null,"key_metric_grain_contributor":false,"metric_component":null}],"key_metric":"pct_of_tract_population","usage":"Pin one grade_level: each row holds for that grade only, and a tract's zones at one grade split its people without overlap (across levels and districts). zone_level follows from the grade (k-05 elementary, 06-08 middle, 09-12 high in most districts; some districts differ), so to list a tract's middle-school zones pin a middle grade such as 07 rather than zone_level alone. To roll a tract count up to a zone at that grade, multiply each tract's count by pct_of_tract_population and add over the zone's rows; to roll up a tract rate, weight it by pct_of_zone_population. Never add num_tract_population across rows.","limitations":"Covers the districts whose zones were collected: a tract in a district without zones at a grade, or in a gap, has no rows there or rows whose population shares add to less than 1. Gaps include areas the zones topic leaves unassigned on purpose: new schools not yet in the schools dimension (their zones are withheld), placement areas whose students are placed among several schools, and closed schools' former areas that no published map reassigns; see the zones topic's coverage table. Some zones are known to predate an adopted boundary change (currency_status stale_known_changes on the zones topic) and carry that error here. Weights are the 2020 census: the share of a tract in each zone is frozen at April 2020, so it misses growth since then, which is largest where new schools and rezonings are. A block that a zone line or a gap's edge crosses is split by area, assuming its people are spread evenly over its land. A block counts toward the district whose current TIGER/Line outline holds its 2020 interior point (the 2020 Block Assignment File where no outline does), as a point lookup answers. Rows are school rows: every row has a district, school and tract.","null_semantics":{"suppressed_to_null":false,"zero_is_real":true},"available_years":[2027],"schema_hash":"122ef0833a4de865c83c1bf2eb5923a1dae32d5677f8ef36e9a6257272409379","tags":["education","school attendance zones","school_attendance_zone_tracts"],"granularity_description":"One row per year, district_code, school_code, grade_level, tract_geoid.","example_queries":[{"description":"Latest year (2027), schools detail","query":"SELECT * FROM school_attendance_zone_tracts WHERE year = 2027 LIMIT 100"},{"description":"District 667 in 2027","query":"SELECT * FROM school_attendance_zone_tracts WHERE district_code = '667' AND year = 2027 LIMIT 100"},{"description":"Filter by zone_level = elementary","query":"SELECT * FROM school_attendance_zone_tracts WHERE zone_level = 'elementary' AND year = 2027 LIMIT 100"}],"foreign_keys":[{"column":"district_code","target_object":"districts","target_columns":["district_code"],"attribute_columns_added":["district_name","district_census_id","district_type"],"scope":"domain"},{"column":"school_code","target_object":"schools","target_columns":["district_code","school_code"],"attribute_columns_added":["school_name"],"scope":"domain"},{"column":"tract_geoid","target_object":"tracts","target_columns":["tract_geoid"],"attribute_columns_added":["tract_name"],"scope":"global"}],"filters":[{"param":"year","kind":"year_exact","type":"integer","multi_value":false,"enum_enforced":false,"values":null},{"param":"year_min","kind":"year_range","type":"integer","multi_value":false,"enum_enforced":false,"values":null},{"param":"year_max","kind":"year_range","type":"integer","multi_value":false,"enum_enforced":false,"values":null},{"param":"detail","kind":"detail","type":"string","multi_value":false,"enum_enforced":true,"values":["schools"],"default":"schools"},{"param":"district_code","kind":"foreign_key","column":"district_code","type":"string","multi_value":true,"enum_enforced":false,"values":null},{"param":"school_code","kind":"foreign_key","column":"school_code","type":"string","multi_value":true,"enum_enforced":false,"values":null},{"param":"tract_geoid","kind":"foreign_key","column":"tract_geoid","type":"string","multi_value":true,"enum_enforced":false,"values":null},{"param":"zone_level","kind":"categorical","column":"zone_level","type":"string","multi_value":true,"enum_enforced":true,"values":["elementary","high","middle"],"has_total":false,"total_value":null,"requires_single_value":false,"nullable":false,"null_filter_token":null},{"param":"grade_level","kind":"categorical","column":"grade_level","type":"string","multi_value":true,"enum_enforced":true,"values":["01","02","03","04","05","06","07","08","09","10","11","12","k"],"has_total":false,"total_value":null,"requires_single_value":true,"nullable":false,"null_filter_token":null},{"param":"is_largest_zone_for_tract","kind":"categorical","column":"is_largest_zone_for_tract","type":"boolean","multi_value":true,"enum_enforced":false,"values":null,"has_total":false,"total_value":null,"requires_single_value":false,"nullable":true,"null_filter_token":null},{"param":"district_type","kind":"dimension_attribute","dimension":"districts","column":"district_type","type":"string","multi_value":true,"enum_enforced":true,"values":["commission_charter","resa","standard","state_agency","state_charter","state_school","state_special"]},{"param":"school_level","kind":"dimension_attribute","dimension":"schools","column":"school_level","type":"string","multi_value":true,"enum_enforced":true,"values":["elementary","middle","high","k12","other"]},{"param":"locale","kind":"dimension_attribute","dimension":"schools","column":"locale","type":"string","multi_value":true,"enum_enforced":true,"values":["city","suburb","town","rural"]}],"filter_hints":[{"primary":"grade_level","dependent":"zone_level","note":"zone_level follows from grade_level: a level's rows exist only at that level's grades (middle at 06-08 in most districts), so pin a grade of the level wanted."}],"non_additive":[{"column":"grade_level","reason":"Every grade's rows assign the same 2020 residents again (a tract's people are counted once per grade), so a count summed across grade_level counts them up to 13 times. Pin one grade."},{"column":"school_code","reason":"num_tract_population is the tract's whole 2020 population, repeated on each zone's row for the tract, so summed across schools or districts it counts the tract again for every zone that touches it.","metrics":["num_tract_population"]},{"column":"district_code","reason":"num_tract_population is the tract's whole 2020 population, repeated on each zone's row for the tract, so summed across schools or districts it counts the tract again for every zone that touches it.","metrics":["num_tract_population"]}],"value_implications":[],"values_endpoint":"/api/v1/education/school_attendance_zone_tracts/values"}