Household incomes in India’s financial capital are rising the fastest. Yet, most families there can’t afford a home.

Mumbai is an exception among big Indian cities where home ownership has become largely affordable, according to JLL India.

On April 01, the real estate services firm released its home purchase affordability index, which shows that the average annual household income in Mumbai falls 16% short of the minimum income required to qualify for a bank loan on a 1,000-square-feet apartment at prevailing market prices.

This is primarily due to Mumbai’s sky-high real estate prices. A property of the same size is more expensive in the coastal city than elsewhere, forcing families to apply for bigger loans that require a higher level of minimum income for eligibility.

(The above chart shows how much higher or lower the average annual household income in a city is compared to the minimum income required to qualify for a home loan on a 1,000-square-feet apartment at the prevailing market prices.)

In 2013, Hyderabad had been the only major city where average household income was above the minimum eligibility criterion for a home loan. As incomes have grown faster than residential prices since then, all except Mumbai have an affordable housing market today.

Incidentally, Mumbai’s household income growth rate has been the highest. This has had a major positive impact on the ability of families to take out home loans: In 2013, the average household in Mumbai was earning just 47% of the minimum income required to qualify for a home loan, as compared to 84% today.

Yet, home ownership will not become a reality for a majority of the city’s households till at least 2021, JLL said.

According to the 2011 census, with 18.4 million residents, Mumbai is India’s most populous metropolitan region. It is also home to one of Asia’s biggest slums, alongside some of the continent’s priciest real estate.