How can i make two functions into one ?

How can i make two functions into one ?

Change and Ready function are duplicating. can i make it one ?


$("#aus_state").css("display", "none");


$("#company_country").change(function(){
var country = $("#company_country option:selected").text();
if(country == 'Australia'){
$("#other_state").css("display", "none");
$("#aus_state").css("display", "block");
$("#company_post_code").attr("maxlength","4");
}
else{
$("#other_state").css("display", "block");
$("#aus_state").css("display", "none");
$("#company_post_code").attr("maxlength","10");
}
});

$("#company_country").ready(function(){
var country = $("#company_country option:selected").text();
if(country == 'Australia'){
$("#other_state").css("display", "none");
$("#aus_state").css("display", "block");
$("#company_post_code").attr("maxlength","4");
}
else{
$("#other_state").css("display", "block");
$("#aus_state").css("display", "none");
$("#company_post_code").attr("maxlength","10");
}
});