To ask the Secretary of State for Work and Pensions if he will estimate how many (a) UK and (b) non-UK residents would purchase an additional (i) six and (ii) nine years of national insurance contributions if purchasing those additional years were available only to those who already had (A) between 10 and 15 years, (B) between 15 and 20 years and (C) 20 years or more of qualifying national insurance contributions in each of the next 10 years. (257196)