Why does FPS consistently go above 60 even though it's limited to 60?

Heres the code, picked it up from a video.

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

public class LimitFps : MonoBehaviour
{
    // Start is called before the first frame update
    void Start()
    {
        Application.targetFrameRate = 60;
    }
}