Life Income Fund: formula for Ontario LIFs 
The prescription for calculating the Maximum Annual Withdrawals for a LIF is as follows:
 For fifteen years from the date when the LIF began, one computes the present value of a
$1.00 annual payment, using an annual rate:
Maximum of CANSIM and 6.0%.
 Thereafter, until age 90, compute the present value using 6.0% and add this to the above giving a number we'll call PV.
 The Maximum Annual LIF Withdrawal is a percentage of the LIF Balance as of January 1, that
percentage being 1/PV.


Assume:
 A = The age when you began the LIF withdrawals.
 T = your current age.
 J = 0.060 ... meaning 6.0%
 K = Canadian Government long bond rate (CANSIM Rate) ... if it's 5.67%, put K = 0.0567
 I = Maximum of J and K ... we're calling this the MAX Rate
 x = 1/(1+I)
 y = 1/(1+J)
 Calculate the Present Value of an annual payment of $1.00 at the rate I, from your current age T to age A+15, namely
P = 1 + x + x^{2} + ... + x^{A+14T} = (1x^{A+15T})/(1x)
 Calculate the Present Value, at age A+15, of an annual payment of $1.00 at the rate J, to age 90, namely
1 + y + y^{2} + ... + y^{90(A+15)}
= (1y^{75A})/(1y) the Value of umpteen $1.00 payments, at age A+15
and, bringing it to the present (A+15T years earlier than at A+15 ... to your present age), gives:
Q = x^{(A+15T)} (1y^{75A})/(1y)
 PV = P + Q
Uh ... one other thing:
If you're over 75 years old then 15 years at the MAX Rate will take y'all over 90,
so don't bother with the MAX Rate; use the 6.0% until age 90.
Here's a picture of the LIF Maxima (as well as RRIF/LIF Minima):
Here's a Spreadsheet formula:
PV = IF(T<=A+14,(1x^(A+15T))/(1x)+x^(A+15T)*(1y^(75A)/(1y),(1y^(90T))/(1y))
... OR, of you just want a spreadsheet which looks like this:
then to download
If'n you'd like just a number, play with this calculator:
