Could this be it? noticed "min": 1, "max": 1,
{ "elements": [ { "type": "area", "width": 2, "dot-style": { "type": "solid-dot", "dot-size": 3, "halo-size": 1, "colour": "#3D5C56" }, "colour": "#3D5C56", "fill": "#3D5C56", "fill-alpha": 0.3, "on-show": { "type": "pop-up", "cascade": 2, "delay": 0.5 }, "text": "", "font-size": 10, "values": [ 1, 1 ] } ], "title": { "text": "Past 30 days PIREPs" }, "y_axis": { "min": 1, "max": 1, "steps": 1 }, "x_axis": { "labels": { "labels": [ "2010-02-21", "2010-02-23" ], "rotate": 270 } }, "bg_colour": "#FFFFFF" }