private double CalculateZoomFactor(int iSize, enumTimeScale timeScale)
{
double dblZoomFactor = ((float) iSize / (float) ((float) (_lEndMillisecond - _lStartMillisecond)/GetMillisecondScale(timeScale)));
if(dblZoomFactor > 10000) dblZoomFactor = 10000;
if(dblZoomFactor < 0.00001) dblZoomFactor = 0.00001;
return dblZoomFactor;
}