Here I have on the screen my country bubbles. Every bubble is a country. The size is population. Here I have children per woman: two children, four children, six children, eight children — big families, small families. The year is 1960. And down here, child survival, the percentage of children surviving Childhood up to starting school: 60 per cent, 70 per cent, 80 per cent, 90, and almost 100 per cent, as we have today in the wealthiest and healthiest countries. But look, this is the world my teacher talked about in 1960: one billion Western world here — high child-survival, small families — and all the rest, the rainbow of developing countries, with very large families and poor child survival. What has happened? I start the world. Here we go. Can you see, as the years pass by, child survival is increasing? They get soap, hygiene, education, vaccination, penicillin and then family planning. Family size is decreasing. They get up to 90-per-cent child survival, then families decrease, and most of the Arab countries in the Middle East is falling down there. Look, Bangladesh catching up with India. The whole emerging world joins the Western world with good child survival and small family size, but we still have the poorest billion. Can you see the poorest billion, those boxes I had over here? They are still up here. And they still have a child survival of only 70 to 80 per cent, meaning that if you have six children born, there will be at least four who survive to the next generation.