data byss;
   input work $ years $ smoke $ status $ count @@;
datalines ;
dusty  <10 yes  yes 30 dusty  <10  yes no  203
dusty  <10 no   yes  7 dusty  <10  no  no  119
dusty >=10 yes  yes 57 dusty >=10  yes no  161
dusty >=10 no   yes 11 dusty >=10  no  no   81
not    <10 yes  yes 14 not    <10  yes no 1340
not    <10 no   yes 12 not    <10  no  no 1004
not   >=10 yes  yes 24 not   >=10  yes no 1360
not   >=10 no   yes 10 not   >=10  no  no  986
; 
run;