File:Proportion of Aged Population (65+) - 2010.png

I calculated the proportion of aged population as the number of aged population over the total number of residents in the subzone. Graduated classification method was also used here as the proportion of aged population in each subzone was not identical, making it less relevant to use categorised as our tool of classification. Graduated was more relevant in this case as it spreads out over a range of values. For the map analysing proportion, I used standard deviation instead of natural breaks as the histogram resembled a normal graph, with an outlier. I classified into 4 groups for each maps, namely, 1. 0 to σ 2. μ - σ 3. μ + σ 4. More than μ + σ

Subzones that have a standard deviation that fall within 0 to σ and more than μ + σ means they differ more from the mean value of proportion of aged population. Most subzones within 0 to σ mainly consists of subzones with less populated subzones like water catchment area or younger estates. Subzones with standard deviation more than μ + σ has a higher population of aged population, meaning it is an older estate. Subzones that have standard deviation closer to mean value means that they have proportion of aged population closer to one another.