unrealistic number for Apple

I read a report today and the analyst is predicting that Apple is going to sell close to 150 million Ipad in 2012 and 2013 and will continue to grow 20% afterwards. It is just unrealistic. The world population is about 6 billion. There are over 4 billion live under $5/day and they are not going to buy an Ipad. It is basically one Ipad for every 10 people if the prediction is correct. （After 20 years growth, the total PC shipments in 2011 is 85 million units). Even if it is achievable, then in 2014, another 110 million units have to be sold to maintain 20% growth. That's a 70% replacement rate (assuming a new Ipad come out). in 2015, it will be 135 million units. This is just impossible. The best reference is ipod. During its best year, it sold 55 million units but it only last for one year. It went back to 40 million units. The total ipod sold in 10 years is about 300 million. And the growth is negative right now. The only way for Apple to maintain its growth rate is have new break though products. Over the last 10 years, it is ipod, iphone and ipad.