how to subtract years from current date in javascript code example

Example 1: javascript subtract days from date

var myCurrentDate=new Date();
var myPastDate=new Date(myCurrentDate);
    myPastDate.setDate(myPastDate.getDate() - 8);//myPastDate is now 8 days in the past

Example 2: subtract 18 years from today javascript

eighteenYearsAgo = new Date();
eighteenYearsAgo = eighteenYearsAgo.setFullYear(eighteenYearsAgo.getFullYear()-18);
console.log(eighteenYearsAgo);