<p>Eighteen million families will be worse off by an average of more than £150 a year from tax and benefit changes over the next two years, unless the Government finds the money to extend last week's 'one-off' income tax cut and to continue topping up the winter fuel allowance, according to analysis by IFS researchers. </p><p> </p><p>The increase in the personal income tax allowance announced on May 13 means that (using Treasury costings) the Government is now giving away £5.5 billion this year through the various income tax, National Insurance, tax credit and benefit changes announced in Budget 2007 and subsequently - the largest such package since the general election year of 2001-02. Of this, around £2.6 billion is being financed through increases in other taxes (including green taxes, capital gains tax, business rates on empty properties and anti-avoidance measures) and around £2.9 billion by increased borrowing. The May 13 'mini-Budget' was a bigger giveaway - if maintained - than in any Budget or Pre-Budget Report since 2001, when the outlook for the public finances appeared much stronger. </p>