I have just over 1/5 of an acre.
The traditional 'quarter acre block' measures:
I have roughly 70% of a quarter acre block.
Details of my block from the Ipswich Council website:
My land value has increased by $20,000, in under 2 years.
Current Google Street View (as at 13 Nov, 2017) - this is from 2 and a half years ago!: