How the results are derived
We averaged the HDB prices for each month by estate across different flat types. This means that if there happens to be more expensive flats transacted for that month, the prices would be higher. Naturally, this could result in greater inaccuracy especially if we attempt to derive an appreciation rate to this, so we averaged out the rate of return per period (in this case, months) to derive a more accurate appreciation across this year.
Here are the results:
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