How to create trendline using adobe flex

Question

I have a bubble chart where i need to draw a trendline on that showing the trend. I have Months on X axis and values (intergers or numerics) on y axis. I have gone through this link http://stackoverflow.com/questions/43224/how-do-i-calculate-a-trendline-for-a-graph , but i'm not able to understand what to use x-axis value and y- axis value and the offset. For example I have values in array collections,

array:arraycollection = new arraycollection([ {month:Jan2000, value:200001},

{month:Feb2000, value:200002},

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{month:Sep2003, value:500001}]);

here I need to show a bubble chart and a trend line on that..... please can anyone help how to do this.....