Though net present value and sets of internal rates of return are completely equivalent criteria for project acceptability decisions, they collectively offer an infinite number of differing implications with regard to levels of project incomes, wealth bases and rates of return. If reinvestment is assumed, there are also sets of average rates of return, equivalent for project acceptability decisions and corresponding, one-to-one, with sets of internal rates and their implications. But the popular constant average and internal rates do not correspond in this way; thus, in general, they differ with regard to project income, wealth base and rate of return implications.