Sir, you are taking my points wrongly...what I am trying to say, SF tag should there against only those trains whose MPS is among the tops in their respective section. SF charge should be same. It's not possible to maintain same speed in every section. Many factors work there- steep gradients, forest areas, soil conditions etc. So why try to implement same rule for every section! Say if you travel on road, 55KMPH is a good speed on an ordinary road, but is it fast enough on a 6 lane National Express Highway?!