The last column in Table 2 and Table 4 are incorrect. Calculating from the values in the other columns the values in the last column of Table 2 are actually, from top to bottom, 1.8 percentage points or 10.5%, 1.8 percentage points or 10.5%, -2.2 percentage points or -2.7%, and -2.3 percentage points or -2.9%. Calculating from the values in the other columns are correct the values
in the last column of Table 4 are actually, from top to bottom, 2.0 percentage points or 17.5%, 2.0 percentage points or 17.5%, 1.6 percentage points or 10.1%, 1.7 percentage points or 10.8%, and 1.4 percentage points or 9.7%.

The author apparently made the incorrect assumption that subtracting two percentage values produces a percentage; it does not. Here is an example:

If my income tax increases from $100 on $10,000 (a tax rate of 1%) income to $200 on $10,000 income (a tax rate of 2%) my income tax has increased by 1 percentage point or 100%–not 1%.