I think you are confused by how it is reported (wonder if that is part of the program). Reported in concentrations, not totality.That's not how you compare number / growth.
You almost got to the right answer but are missing one crucial step. Yes the difference is 0.014%, but that has to be relative to the starting percentage which is 0.028%.
0.014% is 50 percent of 0.028%.
I think what is tripping you up is that there are too many percentage symbols.
Let me give you another analogy.
Think of a nice cheeseburger.
You start off with a 100g patty. The whole burger is 1000g (a lot of bacon and veggies). 10% of burger is patty
You upgrade to a double patty. Now you have 200g of patty. Now around 20% (not exactly 20 but still) of burger is patty.
Would you say that is a 100% increase of patty? Or would you say that is a 10% increase of patty? (which is what you are suggesting with you math.)
It is a 100% increase of patty because it doubled



