{
  transactions (
    filters: {
      buyer_verticals: ["Pharmaceuticals", "Media", "Automotive"],
      buyer_marketCap: {greaterThan: 299999999, lessThan: 57900000001},
      buyer_numberOfEmployees: {greaterThan: 4, lessThan: 50000}
      orderTime: {greaterThan: "2016-09-01 0:0", lessThan: "2017-09-01 0:0"}
    },
    group: ["buyer_vertical", "product_category"]
  ) {
    totalSum: func(field: "totalAmount", op: "sum"),
    product_category
  }
}