productName	dollar_sales
1937 Lincoln Berline	3726.45
1936 Mercedes-Benz 500K Special Roadster	1768.3300000000002
1952 Alpine Renault 1300	5571.8
1962 LanciaA Delta 16V	5026.14
1958 Setra Bus	3284.28

->pipe(new Map(array(
    '{end}' => function($count) {
        $addedRows = [
            ['productName' => 'Number of products: ', 'dollar_sales' => $count],
            ['productName' => 'Total sales: ', 'dollar_sales' => 'Unknown amount'],

        ];
        return $addedRows;
    }
)))