What is the capital gain % difference if sold after 2 years vs less

There is no difference. The tax liability difference is between one year and less. 

Or are you asking about a home sale?

for securities, where the sale is more than 1 year after the purchase and gain or loss is long-term for federal income tax purposes.  the rate is the same regardless of whether it was held two years or ten.  (business property is subject to depreciation recapture before capital gain rates kick in).  many states have different laws. for example, in Illinois, there is no distinction between long-term and short-term. other states have a sliding scale for the tax rate on capital gains depending on how long the security is held.