My parents are from India, and when I visited Delhi around 1980, the air pollution was indeed horrible. However, the 12 years number looks fishy to me, consider

My parents are from India, and when I visited Delhi around 1980, the air pollution was indeed horrible. However, the 12 years number looks fishy to me, considering that according to Wikipedia https://en.wikipedia.org/wiki/List_of_Indian_states_by_life_expectancy_at_birth https://en.wikipedia.org/wiki/List_of_Indian_states_by_life_..., in 2019, the average life expectancy in India was 69.7, compared to 72.9 for Delhi.