I use http://highcharts.com and there is really strange result. So, my data looks like:

Value | Date
1507   2013-02-03
734    2013-02-02
0      2013-02-01
225    2013-01-31 *Graphic miss*
672    2013-01-30 *Graphic miss*
692    2013-01-29 *Graphic miss* <--- This value gone to 1 february
910    2013-01-28
314    2013-01-27

I miss three days (29 January, 30, 31).

When i get data from database, i convert it so:

var lines = [];
                    try {
                        jQuery.each(data, function(i, line) {
                            var dateArr = line.date.split('-');
                            lines.push([
                                Date.UTC(dateArr[0],dateArr[1],dateArr[2]),
                                parseInt(line.num_chips)
                            ]);
                        });
                    } catch(e) { }

Why could it be so? =\