calculate_growth_rate = function (data, date) {
z.sortByCol("publication_year", "asc", data);
var caca = z.gbSum(
"Count",
z.groupBy((d) => d.publication_year, data)
);
var growth = z.getCol("sum", caca);
var zdata = z.pctChange(growth);
return z.addCol("growth", zdata, caca);
}