k12 = d3
.flatRollup(
demo_grade.filter((d) =>
new Set([
...d3.range(0, 13),
"Full-Day Kindergarten",
"Half-Day Kindergarten"
]).has(d.grade)
),
(v) => d3.sum(v, (d) => d.count),
(d) => d.year,
(d) =>
new Set(["African American", "Hispanic", "white", "Total"]).has(d.race)
? d.race
: "other"
)
.map(([year, race, count]) => ({ year, race, count }))