PJ calculated an ex-ante economic internal rate of return (EIRR) in constant terms for all except one of the projects evaluated. On an education project, PJ relied on studies showing that general investment in education has a positive impact, but that no meaningful ERR can be calculated for activities such as compulsory education. This approach means that it is difficult to know whether the proposed investment offers an acceptable economic return. The calculated EIRR for the other projects was generally in the range 9-14%, although the calculated figure for a rail project was only 4%. This was seen as marginal, but acceptable in the light of substantial, unquantified domestic benefits, e.g. from economic regeneration.