Not bad!
Pretty good time waster. I managed to get to 202% but it took nearly half an hour. I lasted that long because the longer the game went, the slower it became, giving me ample time to pick off zombies.
I lost because I wanted to use the elevator trap when the zombies came into the house. Didn't know that once they enter it's game over. T_T Really though, the slowness was irritating.