Data A; incr = 8*atan(1)/100; angle=0; r=5; 
do i = 1 to 101; Y=r*sin(angle); X=r*cos(angle); 
angle = angle + incr; id=1; output; end; 
R=r-.08; id=2; X=0; Y=0; output; X = R; output;  
up = round(50/3.14159); put up; angle=0; 
do i = 1 to up;  Y=r*sin(angle); X=r*cos(angle); 
angle = angle + incr;  output; end; 
X=0; Y=0; output;
axis1 length = 3 inches offset = (.2 inches,.2 inches); 
proc gplot; plot Y*X= id /haxis=axis1 vaxis=axis1 nolegend; 
symbol1 v=diamond i=none; 
symbol2 v=none i=join c=red w=3; 
run;