xAxis: {
                categories: ['Planning', 'Design', 'Development', 'Testing', 'Delivered']
            },

series:
            [
                {
                    "name": "Bla",                          //deze komt onder planning
                    "data": [[-9,10]]
                },
                {
                    "name": "Bla2",                         //deze ook :/ maar deze moet Design worden
                    "data": [[-4,15]]
                }
            ]