Sheffield Electorate Forecast 2010-18 |
MDFS::maps.Sheffield.lgbr2013.Forecast | Search |
This is my projection of individual ward electorates based on Sheffield City Council
and Office of National Statistics/Census figures. I will update it when the City Council
publish the official data, but it is a working set of data to start from.
| Forecast.xls: full Excel spreadsheet.
MethodologyI have projected each ward's electorate using a similar method to the projections I made in 2002. Those projections have turned out to be close to actual reality, and were more accurate than the City Council's initial projections. Based on this I believe that these projections are sufficiently accurate for the task in hand. Sheffield City Council (link) and the Office of National Statistics/Census (link) have published projections of Sheffield's total population from 2011 to 2021. The electorate is a proportion of this total population, essentially the adult population within the full population. That proportion is about 71% of the total population, and has been slowly creeping upwards since before 2000. Projecting from the electorate at 68% of the total propulation in 2000, through 72% in 2013, I have conservatively projected the 2018 electorate to be about 75% of the total population. This is the result of the population as a whole having fewer under-18s compared to over-18s as the general population profile ages. This is confirmed in ONS/Census statistics and projections. That projected total electorate calculated from SCC/ONS/Census projections is very close to the total electorate from summing each projected ward electorate. Each ward's electorate cannot be projected as a simple fraction of the city electorate, as some wards are increasing and some are decreasing, all at different rates. I have projected each ward electorate in isolation from other wards. I have done this by taking a projection from each of the three years prior to 2013 through 2013 to 2017 and 2018. I have then averaged each of these three projections to come to the actual projection. No projection can be 100% accurate, but I am confidant that this is accurate enough for the task in hand, which will be aiming to get ward totals within less than 10%, and ideally less than 5% of each other. Full data is in the Forecast.xls Excel spreadsheet. |