Create a second dataset where every y value is equal to 11 

my $dataref = [ 
     ['2004-01-08','2004-01-09','2004-01-10'], # X-values
     [ 10.9, 10.7, 10.8 ], # Y-value 1
     [ 11,11,11 ], #Y-value 2 reference line
];

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--
Clayton

In reply to Re: Drawing reference lines with GD::Graph by clscott
in thread Drawing reference lines with GD::Graph by phildog

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