Simplify the following text for a Grade 7 native English-speaking person.
Original: On the other hand , the Planning Commission of India uses its own criteria and has estimated that 27.5 % of the population was living below the poverty line in 2004 -- 2005 , down from 51.3 % in 1977 -- 1978 , and 36 % in 1993-1994 .
Simplified: 27.5 % of the population was living below the poverty line in 2004 -- 2005 .