IRRとNPV

NPV net present value,       .
                 ,                110    ,              ,      10%   ,
                 N*(1+10%)=110, N=100 .                    ,               100(   120), 
  NPV=100-120=-20             .           100(  70),   NPV=100-70=30                   30 .
IRR internal rate of return   ,                 ,                           .           . 
           100 ,      30 ,      30 ,     40       40     .                 , 
   15%p.a      IRR.   IRR      .                      IRR     ,             ,    0      , 
          IRR.   IRR               RRR,    IRR            , 
 RRR(required rate of return)              .

  。IRR              。