Code won't show correctly in the browser.

const xhr = new XMLHttpRequest();
xhr.onreadystatechange = function() {
   if(xhr.readystate === 4) {
       const employees = JSON.parse(xhr.responseText);
       const statusHTML = '<ul class="bulleted">';
       for(const i = 0; i < employees.length; i += 1) {
          if(employees[i].inoffice === true) {
           statusHTML += '<li class="in">';   
       } else {
          statusHTML += '<li class="out">';
       }
       statusHTML += employees[i].name;
       statusHTML += '</li>';
     }
     statusHTML += '</ul>';
     document.getElementById('employeeList').innerHTML = statusHTML;
   }
};
xhr.open('GET', 'data/employees.json');
xhr.send();