The behind-the-screen formula is tweaked on a regular basis, to account for new evidence.

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The reason is that companies are selected on the basis of a complex formula of size, liquidity and sectoral representation.

ECONOMIST: Europe��s index wars

In NAMA, the basis of the draft text is a formula connecting new tariffs to old ones.

ECONOMIST: World trade

He wants funding for Scotland to be on the basis of a needs assessment, not the formula which bears his name.

BBC: Scotland Bill part two

He is battling now against a French attempt to call a conference in Paris next month on the basis of Mr Obama's formula that so annoyed him last month: that the starting point should be the 1967 line, with mutually agreed land swaps and security provisions.

ECONOMIST: Israel and diplomacy

Formula penalties in a special program may be lower or higher than the IRS would assess on an individual basis.

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