jpgraph双Y轴问题

Hi so I've been struggling a good while to make the chart I want and I'm getting very close.

First I have performance data of a stock portfolio that should be on YAXIS #1... That's good. Then I want a benchmark on YAXIS #2... The Line plot works, but the scale is weird :

Notice how it starts at 50 and goes 10, 15, 20, etc... The thing is the scale should be between 3400 and 3800 since that's the range of my data.

Here is my code :

    <?php // content="text/plain; charset=utf-8"
require($_SERVER['DOCUMENT_ROOT'] . '/wp-blog-header.php');
require_once ('jpgraph.php');
require_once ('jpgraph_line.php');
require_once ('jpgraph_date.php');
require_once ('jpgraph_utils.inc.php');

// Get a dataset
$data = get_transient( 'daily_nav' );
$ydata = $data[1];
$xdata = $data[0];

$data2 = get_transient( 'CAC40_history' );
$ydata2 = array_reverse($data2[1]);
$xdata2 = array_reverse($data2[0]);


$dateUtils = new DateScaleUtils();
list($tickPositions, $minTickPositions) = DateScaleUtils::GetTicks($xdata);

// Setup a basic graph
$width=800; $height=500;
$graph = new Graph($width, $height);
$graph->SetScale('datlin');

$graph->SetYScale(0,'lin');
$graph->SetYScale(1,'lin');

$graph->SetMargin(60,20,40,60);
$graph->xaxis->SetPos('min');
$graph->xaxis->SetTickPositions($tickPositions,$minTickPositions);

// Setup the titles
$graph->title->SetFont(FF_GEORGIA,FS_NORMAL,16);
$graph->title->Set('Performance vs. CAC40');
$graph->subtitle->SetFont(FF_ARIAL,FS_ITALIC,10);
$graph->subtitle->Set('graphique journalier depuis la création en juin 2012');

// Setup the labels to be correctly format on the X-axis
$graph->xaxis->SetFont(FF_ARIAL,FS_NORMAL,8);
$graph->xaxis->SetLabelAngle(30);

// The second paramter set to 'true' will make the library interpret the
// format string as a date format. We use a Month + Year format m-d-Y
$graph->xaxis->SetLabelFormatString('m-Y',true);


// And then add line. We use two plots in order to get a
// more distinct border on the graph
$lp2 = new LinePlot($ydata,$xdata);
$lp2->SetColor('#71a7da');
$graph->Add($lp2);
$graph->xgrid->Show();
$graph->AddY(0,$lp2);

// second chart
$lp3 = new LinePlot($ydata2, $xdata2);
$lp3->SetColor('blue');
//$graph->Add($lp3);
//$graph->xgrid->Show();
$graph->AddY(1,$lp3);


// And send back to the client
$graph->Stroke();
?>

Would be great if anyone can help, can't figure this one out. Thanks

I am quite a newbie but had the same issue myself a minute ago. Missing zeros on the right? Try changing margin settings?

$graph->SetMargin(60,50,40,60);