function checkform () 
{ 
var form = document.forms[0]
if (form.income.value == "") { 
alert( "please enter your current income" ); 
form.income.focus(); 
return false ; 
} 
if (form.percent.value == "") { 
alert( "please enter percentage of Income Protection"); 
form.percent.focus(); 
return false ; 
} 
if (form.year.value == "") { 
alert( "please enter years of income provision"); 
form.year.focus(); 
return false ; 
} 
if (form.insured.value == "") { 
alert( "please enter total sum insured"); 
form.insured.focus(); 
return false ; 
} 
if (form.inflation.value == "") { 
alert( "please enter estimated annual inflation"); 
form.inflation.focus(); 
return false ; 
} 
if (form.rate.value == "") { 
alert( "please enter return rate"); 
form.rate.focus(); 
return false ; 
} 
return true ; 
}