Concrete is one of the oldest building materials in human history. It’s been used since ancient times. It’s made of three components, it’s very simple. It’s made of aggregate, sand and cement. And people often confuse cement with concrete and interchange those words. Cement is part of concrete but it’s not concrete. And I’ll say two things about concrete. When I was young, people told me never try to paint it because it doesn’t like to be painted or coated. Which caused me to go into the (cement coating) concrete coatings business. Also, I took a seminar once in which I was informed that concrete, although it’s well understood, still fails at a very high rate. Structures that were built 2000 years ago still stand and bridges collapse that were built in our lifetime. So we don’t completely understand, even though it’s a simple process, the actual complexities of concrete, we’re still learning.