Hello, Can you please provide me some idea, why my code does not add the $ sign to the yAxes ticks on the ChartJs Column chart?

ColumnChart::create(array(
	"dataStore"=>$this->dataStore("data"),
	"columns" => array(
	    "month",
		"amountSum"=>array(
			"label" => "Revenue",
			"type" => "number",
			"prefix" => "$ "
		)
    ),
    "options" => array(
        "scales"=>array(
        	"Axes"=>array(array(
            	"ticks"=>array(
            		"callback"=>function($value, $index, $values) { return "$ ".$value;}
            	)
            	)
            ))
        )
    )

);

The chart still looks like this:

Thanks for your support in advance!

Unfortunately it did not help

You are great. Now it works perfectly. Many thanks!