if you wish to invest in the government bonds then you can check the websites of National Highways Authority of India [NHAI] and Rural Electrification Corporation [REC]
above table i got from the website called cleartax
it gives the cost inflation index values for different years beginning from 2001
what is indexation?
you must have purchased the property at a certain cost price
as time passes by, the value of money goes down. This is known as inflation
so the cost price of your property would also devalue
to account for the same, the cost price is indexed i.e. it is increased on a proportionate basis to adjust for inflation
when you calculate the capital gains tax on sale of your property, you are allowed to deduct the indexed cost of acquisition from it. There are other deductions as well. After making all these deductions, you arrive at your capital gains on which you have to pay capital gains tax
had you simply deducted the cost price (without indexing it), the capital gains value would be more and you would have to pay more tax
so the government allows to index the cost of acquisition such that the cost price is increased to account for inflation
as due to indexation, the capital gains value reduces, the tax rate is 20%
whereas if no indexation is done, the capital gains value comes high, and that is why tax rate is kept at 10%
for calculating indexed cost of acquisition, you have to take CII for the year 2001 which is 100 as given in table above
then you take the CII of the year of sale
now: Original cost price corresponds to CII of base year 2001
so today's cost price adjusted for inflation (assume it is X) would correspond to CII of year of sale, say 280
you do simply cross multiplication as under:
Therefore X (indexed cost of acquisition) = original cost price x CII of year of sale (280) / CII of base year (100)
the formula is given as under. Accordingly you get indexed cost of acquisition
Kindly consult a CA for exact figures to determine your tax liability