RealData's Bubble Index scores a condo's asking price against the median price-per-sqm of its district: 100 is on par, above 100 is overpriced, below 100 is underpriced.
We take each building's median sale price-per-sqm from active listings and divide it by the district median, indexed to 100. A reading of 115 means the building asks ~15% above its district; 85 means ~15% below. Stored as value_scores.bubble_index.