<!--

function doDOBcal()
 {
  dob1 = parseInt(document.DOBcal.dob1.value)
  dob2 = parseInt(document.DOBcal.dob2.value)
  dob3 = parseFloat(document.DOBcal.dob3.value)

  if( dob1 > 0 && dob2 > 0 && dob1 < dob2 && dob3 > 0 )
    {
     x = dob3 * 24 / (Math.log(dob2/dob1) / Math.LN2)
     x = Math.round(10*x) / 10
     document.DOBcal.dt.value  = x 

    x = dob3  / (Math.log(dob2/dob1) / Math.LN2)
     x = Math.round(10*x) / 10
     document.DOBcal.inc.value  = x 
    }
//   else
//    {
//    }

  return false
 }
// -->