4.1 The differences between the latest sub-national projections and the previous 2010-based projections are summarised in Table 5 which compares the populations of administrative areas under the two projections at selected years (2012, 2017, 2022, 2027, 2032 and 2035).
4.2 The 2010-based projection showed Scotland’s population to be 5.28 million by 2012 compared with the 2012 mid-year population estimate of 5.31 million. It is important to note that the 2010-based population projections did not incorporate results from the 2011 Census while the 2012–based projections did include information from the 2011 Census. In addition, in the intervening two years the birth rate has reduced slightly and there has been a fall in net migration. National Records of Scotland’s population estimates have been rebased with information from the 2011 Census which meant that the base population used in the projections was higher by about 49,000 to what had been previously estimated. So while the overall population projection total for the next 25 year period is very similar to that projected for the 2010-based projections, the underlying demographic trends differ and the base population has taken into account information from the 2011 Census. More information on the differences between the rolled forward estimates from 2001 for 2011 and those from the 2011 Census are available in the 2011 Census Reconciliation Report on the NRS website. There are relatively similar differences by administrative areas under the two sets of projections. These differences are seen in Figure 8 and Figure 9 which show the percentage difference between the 2010 and 2012- based population projections in the population projected for 2035, which was the last year of the 2010-based projections. These differences highlight that projections become more uncertain the further ahead you go, and illustrate that it is worth producing new projections on a regular basis.
4.3 Figure 8 shows that, by 2035, the population in 18 of the Council areas is higher under the 2012-based projection than under the 2010-based projection. The biggest differences in the projected population for 2035 between the different sets of projections are in Clackmannanshire, Shetland Islands, and Dundee City. Figure 9 shows that by 2035 eight NHS Boards1 have higher populations under the 2012-based projection, namely Western Isles, Orkney, Greater Glasgow & Clyde, Dumfries & Galloway, Grampian, Ayrshire & Arran, and Tayside. These changes have come about again because of the different starting point in the 2012 mid-year estimate and because of the changes to the fertility, mortality and migration assumptions. When looking at the comparisons between the projections it is important to bear in mind the uses and limitation of projections described in Section 2. More details about the assumptions can be found in Section 6.
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