I'm trying to generate a pie graph with Sparklines but I'm running into some trouble. I can't seem to figure out what I'm doing wrong, but I feel it is a silly mistake.

I'm using the following code to generate a sparkline chart in the div #traffic_bos_ss:

//Display Visitor Screen Size Stats
$.getJSON('models/ucp/traffic/traffic_display_bos.php',
{   
    type: 'ss',
    server: server,
    api: api,
    ip: ip,
},
function(data)
{
    var values = data.views;
    //alert(values); 


    $('#traffic_bos_ss').sparkline(values,
    {
        type: "pie",
        height: "100%",
        tooltipFormat: 'data.screen - {{value}}',

    });
});

The JSON string fetched:

{"screen":"1220x1080, 1620x1080, 1920x1080","views":"[2, 2, 61]"}

For some reason Sparklines does not process the variable values. When I alert the variable it outputs "[2, 2, 61]". Now the jQuery code does work when I replace the snippet:

 var values = data.views;

with

 var values = [2, 2, 61];

What am I doing wrong?