Therefore, the impact of including non-Scottish domiciled residents in the denominator is minimal.
The relevant law is complex and depends on whether the parties are "domiciled" (legally resident) in England or one of them can demonstrate a form of habitual residence in England or Spain.
A non-domiciled resident is someone that is born outside the UK and now lives here, but intends to return to their home-country.
Goldsmith senior was a non-domiciled resident in France who denied both Britain and France the chance to tax his estate.
And yesterday Gordon Brown gave the strongest indication yet that the government will move to close tax loopholes used by private equity firms and the non-domiciled resident rich.
Lord Ashcroft, a multimillionaire who made much of his fortune in the Caribbean, had previously given up his status as a non-domiciled resident in the UK in 2010 in order to retain his seat in the House of Lords following a ruling that all members had to be fully UK-resident for tax purposes.
Another was the strange support for institutionalised aristocracies – including, to my mind, such related phenomena as the monarchy, a tax system of unequal benefits for the "non-domiciled" resident rich, and an economic model dependent on a financial services industry whose participants privatise the profits of risks borne publicly.
Cushy treatment of non-domiciled residents helps, he says.
At its heart is a generous tax exemption for non-domiciled residents, or "non-doms", who need have only tenuous links to another country.
This is a peculiarly British rule whereby foreigners, or Britons who can claim to be, together known as "non-domiciled residents", enjoy special tax exemptions.
The Labour government elected in 1997 kept the city attractive with stable economic management and with corporate and income taxes that were low, at least by French standards though these are set to rise for non-domiciled residents.
