Ok, the thing is, it appears that my employer already took out the additional tax I owe:
1) For the first $200,000, I paid $2,900 (1.45%)
2) For the rest of my wages over that ($96,409), I paid $2,265.61 (2.35% which is 1.45% + the extra .9%)
3) Total Medicare taxes I paid: $5,165.61. This matches Box 6 on my W2.
So I'm not sure why I'm now liable for an extra $868 per Form 8959. $868 is .9% of my excess wages over $200,000. But like I mentioned, it appears that my employer already withheld the extra .9% (See item #2 I listed above.)
