#xnpv

[masterexcelstuff-blog]

Excel Magic Trick 1430 DESCRIPTION See how to use the DAX Functions XNPV and XIRR to calculate the Net Present Value and Internal Rate of Return of Cash Flows that occur at irregular date intervals. WORKBOOKS

[mrfebird]

NPV - when cash flow received at the beginning

Just treat it as cash flow received at the end of period and then multiple by (1+r), as you discounted the cash flow by one extra year if using NPV formula, which mean you divided (1+r) for the cashflow. 

XNPV will be for cashflow in irregular intervals.