KoolChart can handle the negative value.
span style="color: #808080; font-style: italic;">/*
* This file is ready to run as standalone example. However, please do:
* 1. Add tags <html><head><body> to make a complete page
* 2. Change relative path in $KoolControlFolder variable to correctly point to KoolControls folder
*/
$KoolControlsFolder = "../../../../KoolControls";//Relative path to "KoolPHPSuite/KoolControls" folder
"/KoolChart/koolchart.php""chart");
$chart->scriptFolder=$KoolControlsFolder."/KoolChart";
$chart->Height = 450;
$chart->Width = 500;
$chart->Title->Text = "Bar Chart with negative values""";
$chart->PlotArea->XAxis->MajorTickSize = 2;
$chart->PlotArea->YAxis->Title = """#399C48""#28A1DA""chart_scatter""/KoolChart""ScatterLine with negative values""""""#90B720""{0},{1}""Above""{0},{1}""#90B720""orange""{0},{1}""Above""{0},{1}""orange""form1" method="post""color:#B8305E;" target="_blank" href="http://codegen.koolphp.net/generate_koolchart.php"
KoolChart - Excellent PHP Chart and GraphFullVersion 1.0.0.0 released on 11/29/2012