csv_data = d3.csvParse(await FileAttachment("states_node_measures_1910_1920.csv").text(),({STATE_FIPS, STATE_NAME, TotalFlow_1910_1920, Inflow_1910_1920, Outflow_1910_1920}) => [+STATE_FIPS, [STATE_NAME, +Inflow_1910_1920/+TotalFlow_1910_1920, +Outflow_1910_1920/+TotalFlow_1910_1920]])