goptions targetdevice = ps;
data a; x=0; f1=0; f2=0; f3=0; output;
lagff1=0; lagff2=0; lagff3=0; 
lagff4=0; lagff5=0; lagff6=0;
lagff7=0; lagff8=0; 
 do x=.1 to 6 by .05; 
   ff1=probf(x,5,20,0);  f1=ff1-lagff1;
   ff2=probf(x,5,20,1); f2=ff2-lagff2;
   ff3=probf(x,5,20,2); f3=ff3-lagff3; 
   ff4=probf(x,5,20,3); f4=ff4-lagff4;   
   ff5=probf(x,5,20,4);  f5=ff5-lagff5;
   ff6=probf(x,5,20,5); f6=ff6-lagff6;
   ff7=probf(x,5,20,10); f7=ff7-lagff7; 
   ff8=probf(x,5,20,20); f8=ff8-lagff8;
keep f1 f2 f3 f4 f5 f6 f7 f8 x;
output; 
lagff1=ff1; lagff2=ff2; lagff3=ff3;
lagff4=ff4; lagff5=ff5; lagff6=ff6;
lagff7=ff7; lagff8=ff8;   end; 
 proc print; 
 goptions vsize=4 horigin=1; 
proc gplot uniform; title "Power"; 
plot (f1 f2)*x/overlay href=2.71;
plot (f1 f3)*x/overlay href=2.71;
plot (f1 f4)*x/overlay href=2.71;
plot (f1 f5)*x/overlay href=2.71;
plot (f1 f6)*x/overlay href=2.71;
plot (f1 f7)*x/overlay href=2.71;
plot (f1 f8)*x/overlay href=2.71;
symbol1 v=none i=join w=2; 
run;