What to mine only shows a very limited selection of cards - they have major space limits, it's not practical for them to show ALL currently profitable cards.
The cards they do show are intended to be a "representative sample" of widely used cards more than anything else.
Also, the figures they use for each card model are often OFF from actual production figures, depending on the specific card and the specific settings for the card - again, "representative sample" ballpark figures not YOUR actual numbers.
They DO let you put in your REAL numbers though fairly easily.