The percentage of likelihood you will be stuck in same economic class as your parents

I'm translating a graph from CNN:

There is a 26% chance you will be stuck in the same class as your parents in Australia
"               32%                                               "                                                   Germany
"               34%                                               "                                                   Japan
"               46%                                               "                                                   Pakistan
"               47%                                               "                                                   USA

So, basically this means that you have almost a 1 in 2 chance of being stuck in the same economic class as your parents were in the U.S. as you move into becoming an adult in the U.S. which is a worse statistic than Pakistan. This is completely different than in the 1960s where we likely would have been the most likely of any country on earth to rise to the top or at least to a higher economic class than our parents. In other words in the 1950s and 1960s we likely were about where Australia is now or better percentage wise.

Source: Your Money on CNN TV Saturday December 14th 2013

Note: Only Italy and Great Britain have less economic mobility than the United States does now in all of Europe.