Tatton: New Boundaries Calculation

Due to changes in ward boundaries, some new wards are divided among several old constituencies (though never between two new constituencies). Such wards are shown divided into several parts, called [1], [2], and so on.

Election results from a recent local election are given. This is usually the local election from 2003, 2004 or 2006. For multiple-member wards, the votes shown are the sum of the votes cast for all candidates of each party. A negative number indicates candidate(s) elected unopposed. Where zero votes are shown, the ward is not needed because the entire old seat is unsplit.

Calculation method: There are two problems with using the raw (actual) local election results to imply general election results ward-by-ward. Firstly, turnout can be different between local and general elections, which means that the total number of local votes cast does not equal the number of votes cast in each old seat at the general election. To correct for this, we adjust the local votes to match the general election turnout. Each ward's result is scaled, whilst keeping constant the percentage support for each party, so that the total turnout adds up to the old seat's general election turnout. All wards in the old seat are assumed to have the same percentage turnout.

Secondly, even though we now have the correct number of votes in the old seat, the party totals will not match the general election result. Some parties do better at the local election than the general election, and others do vice versa. We call these strong and weak parties respectively. The next step is to transfer votes from strong parties to weak parties. This is done by taking votes proportionally away from strong parties and putting them in a transfer pool. For instance if a party got 12,500 local votes, but only 10,000 general election votes, it will lose 20% of its votes from each ward. These votes in each ward will be put in the ward's transfer pool and allocated to the weak parties. Weak parties will get votes transferred to them in proportion to the votes they need over the old seat. For instance, if two weak parties need 4,000 and 1,000 votes respectively, the first party will get 80% of each ward's transfer pool and the second party will get 20% of each ward's transfer pool. The transfer of votes between parties is done on a ward-by-ward basis using these common percentages.

More details of the calculation formulas are available.

The old seat(s) needed are:

• Weaver Vale
• Tatton

Old seat: Weaver Vale

					Actual Results				Turnout-adjusted Results					Transfer-adjusted Results
District	Ward	Electorate 2005	Old Seat	New Seat	CON Votes	LAB Votes	LIB Votes	OTH Votes	CON Votes	LAB Votes	LIB Votes	OTH Votes	Total Votes	CON Votes	LAB Votes	LIB Votes	OTH Votes	Total Votes
Halton	Beechwood	3,276	Weaver Vale	Weaver Vale	376	576	1,807	0	255	391	1,228	0	1,874	267	396	1,209	0	1,874
Halton	Castlefields [2]	4,413	Weaver Vale	Halton	300	2,694	369	672	188	1,686	231	421	2,526	401	1,785	227	111	2,526
Halton	Daresbury	3,192	Weaver Vale	Weaver Vale	984	627	1,051	0	675	430	721	0	1,826	682	433	710	0	1,826
Halton	Halton Brook [2]	0	Weaver Vale	Halton	366	2,444	690	0	0	0	0	0	0	0	0	0	0	0
Halton	Halton Lea	4,882	Weaver Vale	Weaver Vale	258	2,265	351	697	202	1,772	275	545	2,794	478	1,900	270	144	2,794
Halton	Mersey [2]	0	Weaver Vale	Halton	309	1,711	2,611	0	0	0	0	0	0	0	0	0	0	0
Halton	Norton North	5,017	Weaver Vale	Weaver Vale	263	2,090	2,897	269	137	1,087	1,507	140	2,871	222	1,126	1,484	37	2,871
Halton	Norton South	4,976	Weaver Vale	Weaver Vale	229	2,539	0	816	182	2,017	0	648	2,847	506	2,167	0	172	2,847
Halton	Windmill Hill	1,707	Weaver Vale	Weaver Vale	58	256	257	0	99	438	440	0	977	103	440	433	0	977
Vale Royal	Forest	1,756	Weaver Vale	Weaver Vale	465	121	0	0	797	207	0	0	1,004	797	207	0	0	1,004
Vale Royal	Frodsham North	5,565	Weaver Vale	Weaver Vale	747	1,752	1,422	1,979	403	946	767	1,068	3,184	946	1,198	755	284	3,184
Vale Royal	Frodsham South	1,769	Weaver Vale	Weaver Vale	308	126	201	0	491	201	320	0	1,012	494	202	315	0	1,012
Vale Royal	Hartford & Whitegate [2]	4,331	Weaver Vale	Weaver Vale	3,605	724	590	0	1,816	365	297	0	2,478	1,819	366	292	0	2,478
Vale Royal	Helsby	3,808	Weaver Vale	Weaver Vale	1,133	428	0	0	1,582	597	0	0	2,179	1,582	597	0	0	2,179
Vale Royal	Kingsley	1,667	Weaver Vale	Weaver Vale	287	33	417	0	371	43	540	0	954	376	45	531	0	954
Vale Royal	Leftwich & Kingsmead [2]	3,091	Weaver Vale	Weaver Vale	1,101	1,287	886	0	595	695	479	0	1,769	599	697	471	0	1,769
Vale Royal	Milton Weaver	1,705	Weaver Vale	Weaver Vale	473	87	133	0	666	122	187	0	975	667	122	184	0	975
Vale Royal	Northwich Castle	4,704	Weaver Vale	Weaver Vale	341	1,368	0	363	443	1,777	0	472	2,692	679	1,886	0	125	2,692
Vale Royal	Northwich Winnington	1,969	Weaver Vale	Weaver Vale	0	-1	0	0	0	1,127	0	0	1,127	0	1,127	0	0	1,127
Vale Royal	Northwich Witton	5,208	Weaver Vale	Weaver Vale	0	1,393	337	0	0	2,400	581	0	2,981	5	2,402	572	0	2,981
Vale Royal	Rudheath & South Witton [2]	688	Weaver Vale	Tatton	231	901	0	0	80	313	0	0	393	80	313	0	0	393
Vale Royal	Weaverham	5,168	Weaver Vale	Weaver Vale	1,355	1,825	405	899	894	1,204	267	593	2,958	1,194	1,343	263	157	2,958
	Total		Weaver Vale						9,876	17,818	7,840	3,887	39,421	11,904	18,759	7,723	1,034	39,421

The transfer table below shows the votes cast in the old seat of Weaver Vale at the general election, as well as the total local turnout-adjusted votes. The number of votes to transfer, shown in the fourth and fifth columns, are the difference between the general and local votes. Strong parties will have votes transferred away, and weak parties will have votes transferred into them. The final column describes how votes will be transferred away from or into that party on a ward-by-ward basis. If a party is too strong, it will lose a percentage of its votes in each ward which go into that ward's transfer pool. If a party is too weak, it will gain votes from each ward's transfer pool in proportion to the number of transfer votes it needs over the whole old seat.

Party	General Election 2005 Votes	Local Election Turnout-adjusted Votes	Votes to transfer away	Votes to transfer into	Ward Transfers needed
CON	11,904	9,876	0	2,028	Transfer in 68.3% (= 2028 / 2969) of ward's transfer pool votes
LAB	18,759	17,818	0	941	Transfer in 31.7% (= 941 / 2969) of ward's transfer pool votes
LIB	7,723	7,840	117	0	Transfer away 1.5% (= 117 / 7840) of ward's LIB votes
OTH	1,034	3,887	2,853	0	Transfer away 73.4% (= 2853 / 3887) of ward's OTH votes
Total	39,420	39,421	2,969	2,969

After transfer adjustment, the totals for each party over all the wards match the general election vote in the old seat.

Old seat: Tatton

					Actual Results				Turnout-adjusted Results					Transfer-adjusted Results
District	Ward	Electorate 2005	Old Seat	New Seat	CON Votes	LAB Votes	LIB Votes	OTH Votes	CON Votes	LAB Votes	LIB Votes	OTH Votes	Total Votes	CON Votes	LAB Votes	LIB Votes	OTH Votes	Total Votes
Macclesfield	Alderley Edge	3,941	Tatton	Tatton	1,522	556	0	0	1,862	680	0	0	2,542	1,862	680	0	0	2,542
Macclesfield	Chelford	2,231	Tatton	Tatton	992	173	0	0	1,225	214	0	0	1,439	1,225	214	0	0	1,439
Macclesfield	Dean Row	3,892	Tatton	Tatton	1,260	0	726	0	1,592	0	918	0	2,510	1,592	0	918	0	2,510
Macclesfield	Fulshaw	3,780	Tatton	Tatton	1,178	226	439	303	1,338	257	499	344	2,438	1,426	328	563	120	2,438
Macclesfield	Handforth	6,257	Tatton	Tatton	700	512	0	1,479	1,050	768	0	2,218	4,036	1,618	1,227	413	776	4,036
Macclesfield	Henbury [2]	271	Tatton	Macclesfield	0	0	0	0	0	0	0	0	0	0	0	0	0	0
Macclesfield	High Legh	2,148	Tatton	Tatton	769	0	0	328	971	0	0	414	1,385	1,077	85	77	144	1,385
Macclesfield	Hough	3,826	Tatton	Tatton	1,382	175	549	0	1,619	205	643	0	2,467	1,619	205	643	0	2,467
Macclesfield	Knutsford Bexton	2,103	Tatton	Tatton	0	0	0	0	0	0	0	0	0	0	0	0	0	0
Macclesfield	Knutsford Nether	2,015	Tatton	Tatton	0	0	0	0	0	0	0	0	0	0	0	0	0	0
Macclesfield	Knutsford Norbury Booths	2,154	Tatton	Tatton	0	0	0	0	0	0	0	0	0	0	0	0	0	0
Macclesfield	Knutsford Over	3,930	Tatton	Tatton	0	0	0	0	0	0	0	0	0	0	0	0	0	0
Macclesfield	Lacey Green	2,044	Tatton	Tatton	198	110	764	0	243	135	939	0	1,317	243	135	939	0	1,317
Macclesfield	Mere	1,744	Tatton	Tatton	-1	0	0	0	1,125	0	0	0	1,125	1,125	0	0	0	1,125
Macclesfield	Mobberley	2,066	Tatton	Tatton	691	155	0	194	885	199	0	249	1,333	948	250	46	87	1,333
Macclesfield	Morley & Styal	3,783	Tatton	Tatton	930	0	1,112	288	974	0	1,164	302	2,440	1,051	62	1,220	105	2,440
Macclesfield	Plumley	1,921	Tatton	Tatton	869	109	0	0	1,101	138	0	0	1,239	1,101	138	0	0	1,239
Vale Royal	Barnton	4,403	Tatton	Tatton	333	1,678	872	0	328	1,653	859	0	2,840	328	1,653	859	0	2,840
Vale Royal	Cogshall	1,754	Tatton	Tatton	603	123	0	0	940	192	0	0	1,132	940	192	0	0	1,132
Vale Royal	Lostock & Wincham	3,352	Tatton	Tatton	245	265	941	0	365	395	1,402	0	2,162	365	395	1,402	0	2,162
Vale Royal	Rudheath & South Witton [1]	2,931	Tatton	Tatton	231	901	0	0	386	1,505	0	0	1,891	386	1,505	0	0	1,891
Vale Royal	Seven Oaks & Marston	1,810	Tatton	Tatton	494	136	0	0	915	252	0	0	1,167	915	252	0	0	1,167
Vale Royal	Shakerley	1,859	Tatton	Tatton	490	123	0	0	958	241	0	0	1,199	958	241	0	0	1,199
	Total		Tatton						17,877	6,834	6,424	3,527	34,662	18,781	7,564	7,080	1,234	34,662

The transfer table below shows the votes cast in the old seat of Tatton at the general election, as well as the total local turnout-adjusted votes. The number of votes to transfer, shown in the fourth and fifth columns, are the difference between the general and local votes. Strong parties will have votes transferred away, and weak parties will have votes transferred into them. The final column describes how votes will be transferred away from or into that party on a ward-by-ward basis. If a party is too strong, it will lose a percentage of its votes in each ward which go into that ward's transfer pool. If a party is too weak, it will gain votes from each ward's transfer pool in proportion to the number of transfer votes it needs over the whole old seat.

Party	General Election 2005 Votes	Local Election Turnout-adjusted Votes	Votes to transfer away	Votes to transfer into	Ward Transfers needed
CON	21,447	17,877	0	3,570	Transfer in 39.5% (= 3570 / 9044) of ward's transfer pool votes
LAB	9,716	6,834	0	2,882	Transfer in 31.9% (= 2882 / 9044) of ward's transfer pool votes
LIB	9,016	6,424	0	2,592	Transfer in 28.7% (= 2592 / 9044) of ward's transfer pool votes
OTH	1,235	3,527	2,292	0	Transfer away 65.0% (= 2292 / 3527) of ward's OTH votes
Total	41,414	34,662	9,044	9,044

After transfer adjustment, the totals for each party over all the wards match the general election vote in the old seat.

New seat: Tatton

District	Ward	Electorate 2005	Old Seat	New Seat	CON Votes	LAB Votes	LIB Votes	OTH Votes	Total Votes
Macclesfield	Alderley Edge	3,941	Tatton	Tatton	1,862	680	0	0	2,542
Vale Royal	Barnton	4,403	Tatton	Tatton	328	1,653	859	0	2,840
Macclesfield	Chelford	2,231	Tatton	Tatton	1,225	214	0	0	1,439
Vale Royal	Cogshall	1,754	Tatton	Tatton	940	192	0	0	1,132
Macclesfield	Dean Row	3,892	Tatton	Tatton	1,592	0	918	0	2,510
Macclesfield	Fulshaw	3,780	Tatton	Tatton	1,426	328	563	120	2,438
Macclesfield	Handforth	6,257	Tatton	Tatton	1,618	1,227	413	776	4,036
Macclesfield	High Legh	2,148	Tatton	Tatton	1,077	85	77	144	1,385
Macclesfield	Hough	3,826	Tatton	Tatton	1,619	205	643	0	2,467
Macclesfield	Knutsford Bexton	2,103	Tatton	Tatton	0	0	0	0	0
Macclesfield	Knutsford Nether	2,015	Tatton	Tatton	0	0	0	0	0
Macclesfield	Knutsford Norbury Booths	2,154	Tatton	Tatton	0	0	0	0	0
Macclesfield	Knutsford Over	3,930	Tatton	Tatton	0	0	0	0	0
Macclesfield	Lacey Green	2,044	Tatton	Tatton	243	135	939	0	1,317
Vale Royal	Lostock & Wincham	3,352	Tatton	Tatton	365	395	1,402	0	2,162
Macclesfield	Mere	1,744	Tatton	Tatton	1,125	0	0	0	1,125
Macclesfield	Mobberley	2,066	Tatton	Tatton	948	250	46	87	1,333
Macclesfield	Morley & Styal	3,783	Tatton	Tatton	1,051	62	1,220	105	2,440
Macclesfield	Plumley	1,921	Tatton	Tatton	1,101	138	0	0	1,239
Vale Royal	Rudheath & South Witton [1]	2,931	Tatton	Tatton	386	1,505	0	0	1,891
Vale Royal	Rudheath & South Witton [2]	688	Weaver Vale	Tatton	80	313	0	0	393
Vale Royal	Seven Oaks & Marston	1,810	Tatton	Tatton	915	252	0	0	1,167
Vale Royal	Shakerley	1,859	Tatton	Tatton	958	241	0	0	1,199
	Total			Tatton	18,861	7,877	7,080	1,234	35,055

And these are the implied results for 2005 for the new seat of Tatton.