So, a general corrosion increase will be there like this and the resistance curve will be enclosed in this envelop. If I draw the speed curve, it will be just the reverse. It will be high speed at the beginning dropping to a low value, then again increasing and dropping, increasing and dropping. This is very interesting. First of all, this gives us some indication if we can estimate the, from the measured speed if we can estimate the resistance increase, we know at what point of time we require to maintain the hull; may be a stepping of the hull, removal of foulings even in approved condition may be desirable.