Explanation:

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 The Housing Price Indices (HPIs) are a broad measure of movement of residential property prices observed within a geographic boundary. The first official housing price index for the country named ‘NHB RESIDEX’ was launched in July, 2007 by the National Housing Bank (NHB).
Overtime, the base year has been revised to FY 2012-13 to ensure capturing the latest information and accurately reflect the current economic situation in the country.
Currently, National Housing Bank is publishing NHB RESIDEX for 50 cities on quarterly basis with FY 2012-13 as base year.
Among 50 cities covered are 18 State/UT capitals and 37 Smart Cities.
NHB is not computing the composite all India housing price index as of now. Using population proportion as weights, an all India index as weighted average of city indices has been computed in-house
The Reserve Bank of India (RBI) began compiling a house price index (HPI) in 2007 with a quarterly HPI for Mumbai city (Base 2002-03=100). Since then, it has extended its coverage to 9 more cities, revised its base to 2010-11=100, and started publishing a composite All India HPI. RBI’s quarterly HPI is based on transactions data received from housing registration authorities in ten major cities.