In relation to each financial year a major precepting authority in Wales shall calculate the basic amount of its council tax by applying the formula—
In this section—
are to be construed in accordance with section 33(12); and
Where the aggregate calculated (or last calculated) by the authority for the year under subsection (2) of section 43 above does not exceed that so calculated under subsection (3) of that section, the amount for item R in subsection (1) above shall be nil.
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Regulations under section 43(7) above may make such consequential alterations of the constituents of any calculation required by item P in subsection (1) above ... (whether by adding, deleting or amending items) as appear to the Welsh Ministers to be necessary or expedient.
The Welsh Ministers shall make regulations containing rules for making for any year the calculations required by item T in subsection (1) above; and the billing authorities concerned shall make the calculations for any year in accordance with the rules for the time being effective (as regards the year) under the regulations.
A statutory instrument containing regulations under subsection (5) is subject to annulment in pursuance of a resolution of Senedd Cymru.
Regulations prescribing a period for the purposes of item T in subsection (1) above may provide that, in any case where a billing authority fails to notify its calculation to the precepting authority within that period, that item shall be determined in the prescribed manner by such authority or authorities as may be prescribed.
Any negative amount given by a calculation under subsection (1) above shall be assumed to be nil for the purposes of this Chapter.