之前有碰到这样的疑问，国内关于内部收益率的定义中把IRR分成了两个板块，而二者之间的区别又解释得很模糊。我上外网查到的结果在这里希望跟大家分享一下。
The differences between FIRR and EIRR are that FIRR are usually measured by the private sector whose attention is on return and EIRR by the public sector who focuses on social welfare as a whole. Tax and subsidies are incorporated in FIRR while not in EIRR. Market price is used in the calculation of FIRR while shadow price(根据社会供需关系或机会成本界定，是该物品对社会福利的边际贡献）is used in the calculation of EIRR.
EIRR is always larger than FIRR. In a nutshell, EIRR differs from FIRR because it takes into account the effects of factors such as price controls, subsidies and tax breaks to compute the actual cost projects bring to the whole economy，e.g. if FIRR =8%， EIRR should be around 20%.
希望对大家有所帮助:)