5(1)The cash equivalent derived from Table A, B or C is to be increased by half if in the relevant year—
(a)the car was not used for the employee’s business travel; or
(b)its use for such travel did not amount to more than 2,500 miles.
(2)In relation to a car which for part of the year was unavailable in the sense of paragraph 2 above, the figure of 2,500 is proportionately reduced.
(3)Without prejudice to sub-paragraph (1) above, if in any year a person is taxable under section 157 in respect of two or more cars which are made available concurrently, there shall be increased by half the cash equivalent derived from Table A, B or C in respect of each of those cars other than the one which in the period for which they are concurrently available is used to the greatest extent for the employee’s business travel.
(4)In paragraphs 2 to 4 above references to the cash equivalent which is to be reduced shall be construed as references to the cash equivalent after any increase under this paragraph.