Dynamic Chart Using Google API In Codeigniter 3.0 - codeigniter

Question

I Am using Google API to show the graph depending on my result of month and mount so, I have taken below code to display the graph here i have static values but i want to give dynamic values
<script type="text/javascript" src="https://www.gstatic.com/charts/loader.js"></script>
<script type="text/javascript">
google.charts.load('current', {'packages':['bar']});
google.charts.setOnLoadCallback(drawChart);
function drawChart() {
var data = google.visualization.arrayToDataTable([
['Year', 'Sales', 'Expenses', 'Profit'],
['2014', 1000, 400, 200],
['2015', 1170, 460, 250],
['2016', 660, 1120, 300],
['2017', 1030, 540, 350]
]);
var options = {
chart: {
title: 'Company Performance',
subtitle: 'Sales, Expenses, and Profit: 2014-2017',
}
};
var chart = new google.charts.Bar(document.getElementById('columnchart_material'));
chart.draw(data, options);
}
</script>
And this is my controller
public function overviews()
{
$data['monthlyTotals'] = $this->livemerchant_model->overviews();
if ($this->input->post('transactionMerchant,transactionYear')) {
$data['monthlyTotals'] = $this->livemerchant_model->overviews($this->input->post('transactionMerchant'), $this->input->post('transactionYear'));
} else {
$data['monthlyTotals'] = $this->livemerchant_model->overviews();
}
$this->load->view('overviews', $data);
}
This is My Model
function overviews($theYear='',$theMonth='')
{
$this->db->select("DATEPART(Year, TRANS_TransactionDate) [TheYear], DATEPART(Month, TRANS_TransactionDate) [TheMonth], DATENAME(Month, TRANS_TransactionDate) [TheMonthName], SUM(TRANS_Amount) [TotalAmount]", false);
$this->db->from('BTBL_Transactions');
if ($theYear != '') {
$this->db->where("DATEPART(Year, TRANS_TransactionDate) = '" . $theYear . "'", NULL, FALSE);
}
if ($theMonth != '') {
$this->db->where("DATEPART(Month, TRANS_TransactionDate) = '" . $theMonth . "'", NULL, FALSE);
}
$this->db->group_by("DATEPART(Year, TRANS_TransactionDate), DATEPART(Month, TRANS_TransactionDate), DATENAME(Month, TRANS_TransactionDate)");
$this->db->order_by("1", "asc");
$this->db->order_by("2", "asc");
$this->db->order_by("3", "asc");
$query = $this->db->get();
//echo $this->db->last_query();die();
return $query->result();
}