multiple AJAX responses delay in JAVASCRIPT

<script src="js/jquery-3.4.1.min.js"></script>
<script>
function test() {
var ajaxTime= new Date().getTime();
const xhttp = new XMLHttpRequest();
xhttp.onload = function() {console.log(new Date().getTime()-ajaxTime);}
xhttp.open("GET", "https://api.yuantutech.com/user-web/ws/query/doct/v1/schedule?deptCode=1001&deptName=%E7%89%99%E4%BD%93%E7%89%99%E9%AB%93%E7%A7%91(%E8%A1%A5%E7%89%99)&regMode=1&regType=1&unionId=29&corpId=265&doctCode=000542&doctName=%E9%AB%98%E6%97%AD&doctSchWeek=%E4%B8%80%2C%E4%B8%89%2C%E4%BA%94&subProfessDoctLabel=false&userPlan=1&target=_blank");
xhttp.send();
}
intvaltag=self.setInterval(test,1000);
</script>