You can overly graphs one on top of the other, so my first thought was why not, overly a second graph which only has the two points in question, but with tick marks bolded, and set the size of marks to 0, i.e. so only the axis shows and overlays what you have, with the two ticks bolded.   Another idea to is plot a 2 point graph over the top with the marks labelled as what you want bolded, rather than setting them on the axis.   http://documentation.sas.com/?docsetId=grstatug&docsetTarget=p1pqfzgbuzbpkzn1mrbzhgggvhkz.htm&docsetVersion=9.4&locale=en   You can find a lot of information here: https://blogs.sas.com/content/graphicallyspeaking/   ... View more