Then obviously, what I will do I will design the structure, so that it can survive up to 20 meter high wave. You see, this is how the statistics come; you cannot design for infinite time you have to go statistically. So, there is statistically a probability of what they called return cycle. So, suppose once in 100 years means, you can break it in seconds and if the wave is 10 second, so you know that after so many cycles this wave’s case repeated.
So, let us not go into that detail, because we do not have so much time, but just the point is important that all statistical properties, everything that you may want to know ever, for design becomes known. This is a short term statics there is one more thing I should mention here, what is called long term statistics.