First let us discuss coin flips. A common misconception comes from thinking of a population as frozen in time. If one says that half of group X does thing Y then in any given reasonable period of time, say a year, half the people in group X will really actually do thing Y. If the number does not mean just exactly that then it is meaningless. Consider that a coin can either be heads or tails so a single flip has a 50 50 chance of being heads or tails. Flip 1000 coins, one time and maybe 45% will be heads and 55% will be tails. Do that 1000 times and average the percent that are heads and the percent that are tails and those averages will be close to 50-50. \cite{lewis2012} When one says that a coin flip will on average give heads 49.9% of the them that means that 49.9% of coin flips will be heads.