Can address make a difference to your pension annuity?

The retired middle class in “middle England” appear to be in a less favourable situation than those who live in other places: The pension annuity that they receive from their insurers at retirement is considerably lower.
One of the concepts focuses on favouring annuities that reflect individual circumstances. In other words, those who live in less well-off areas should not support those living in more prosperous areas with better living conditions and longer life expectancy. However this may also show a reverse effect, as post code annuities may lead to a situation when those living in more favourable areas will in fact get more rather than less.
In addition to postcode, age and sex, insurers now take into account lifestyle factors, such as obesity or smoking.
The pensions that MP's get are based on salary instead of annuity. But if the same schemes were applied for MPs’ pensions as in the private sector, their retirement incomes would be much different due to postcodes.
People who are nearing retirement are now faced with the daunting task of having to fill many forms for annuity, including postcode annuity, and seeking advice.
Source: blogs.telegraph.co.uk