data work.disper7b;
        set zone7b.pollen;
        length BarDrill $ 40;
        if pollentype='GRASS' then bardrill='HREF="grass7b.html"';
        if pollentype='WEED' then bardrill='HREF="weed7b.html"';
        if pollentype='TREE' then bardrill='HREF="tree7b.html"';
     run;

     ods listing close;
     ods html path='c:\data\pollen\html' body='sources.html';
     goptions device=gif xpixels=360 ypixels=240;
     proc gchart data=work.disper7b;
        hbar month / sumvar=count group=pollentype discrete
             
     run;

     quit;
     ods html close;
     ods listing;