JS set vs obj performance

set vs obj

var N = 100000000

var theSet = new Set();
console.time()

/***********************************/
for(let i = 0 ; i < N; i++ ) {
    let v = i%20;
    if (!theSet.has(v))
        theSet.add(v);
}
/***********************************/
console.timeEnd()
console.log('section 1 : ');


obj = {};
console.time()
/***********************************/
for(let i = 0 ; i < N; i++) {
    let v = i%20;
    if (!obj[v])
        obj[v] = 1;

}
/***********************************/
console.timeEnd()

console.log('section 2 : ');