title: sas: unable to figure out INTCK function error
body: <p>I am trying to use INTCK in the following manner but get error. I am not sure what I am doing wrong. I would appreciate your help. Thanks.</p>
  
  <pre><code>PROC FORMAT;
  PICTURE DTFMT LOW-HIGH='%0m/%0d/%Y'  (DATATYPE=DATETIME);
  RUN;
  
  data want;
  dt_val1='17JUL2006:00:00:00.000'dt;
  dt_val2='17AUG2012:00:00:00.000'dt;
  format dt_val1 dt_val2 dt_val3 dtfmt.;
  dt_val3=intck('MONTH',dt_val1,dt_val2);
  put dt_val3;
  run;
  </code></pre>