This is a graph of income, not wealth, but since the income that goes to the uberrich seldom leaves them, and they work harder day by day to see that it doesn't (lowering wages, closing shops in high-wage countries to re-open shops in slave-wage countries, buying senators to ensure their taxes are increasingly lowered, etc), we've seen a huge shift in the % of wealth held by the pigs at the deep end of the trough.