Calculation of present value

The table below lists different financial securities and how you can determine the present values of these:

Year	0	1	2...	...t-1	t	t+1	Present Value	When to use?
Perpetuity		1	1...	1	1	1...	\[\large \frac{1}{r}\]	Use this for an infinite series of yearly payments
t-period Annuity		1	1...	1	1		\[\large \frac{1}{r} - \frac{1}{r(1+r)^t}\]	Use this when you get a fixed sum paid each year for <t> periods
t-period Annuity Due	1	1	1...	1			\[\large (1+r)*(\frac{1}{r} - \frac{1}{r(1+r)^t})\]	Same as the t-period annuity but payments start immediatly
Growing Perpetuity		1	\[1*(1+g)\]	\[1*(1+g)^t-2\]	\[1*(1+g)^(t-1)\]	\[1*(1+g)^t\]	\[\large \frac{1}{r-g}\]	Use this for perpetuities where a yearly, growing cost g is involved
Growing Annuity		1	\[1*(1+g)\]	\[1*(1+g)^(t-2)\]	\[1*(1+g)^(t-1)\]		\[\large (\frac{1}{r-g} - \frac{1}{r-g} * \frac{(1+g)^t}{(1+r)^t})\]	Use this for annuities that grow at rate g