= 0; $i-- ) { $time = strtotime( "-{$i} days" ); $date = date( 'M_d', $time ); $chart_data[] = [ 'date' => str_replace( '_', ' ', $date ), 'value' => ! empty( $this->output[ $date ] ) ? floatval( $this->output[ $date ] ) : 0, ]; } return $chart_data; } }