New Delhi: The official back-series estimates for India's GDP released on Wednesday shows a wide divergence with the "unofficial" back-series data released in July by the government.
Compared to the "unofficial" back-series, the official back-series slashed the growth rates for all the seven years under review -- from 2005-06 to 2011-12 -- by 90 basis points in 2009-10 to 250 basis points in 2007-08.
The overall impact is that while the "unofficial" back-series data showed an average annual growth rate of 8 per cent in the nine years between 2005-06 and 2013-14 under UPA regime, the official back-series has cut it down to 6.7 per cent.
With average annual growth rate for four years between 2014-15 and 2017-18 under the NDA rule at 7.4 per cent, the routine exercise of coming up with a back-series immediately after the change in base year has resulted in a political slugfest.
Instead of explaining the divergence between the two back-series, the government said the Congress celebrated the upward revision of rates for 2012-13 and 2013-14 when base year was changed in 2015 but is unhappy with the back-series in 2018.
The base year for calculating the GDP was changed from 2004-05 to 2011-12 in 2015. But it took the government more than three years to come up with a back-series. The official back-series, however, was released only months after the "unofficial" one.
The back-series data by a National Statistical Commission panel headed by Sudipto Mundle released in July 2018 was termed as "not official estimates" by the Ministry of Statistics. The Central Statistics Office (CSO) released the official back-series on Wednesday.
Principal Economic Adviser to the Finance Ministry Sanjeev Sanyal said while the "unofficial" back-series had a kink and the official one did not, it may still have "some issues regarding the use of certain data streams that they have used".
"There was a kink, which was one of the problems with that. Here, I haven't seen any kink but there may be other issues. We have taken certain data...for example, we have introduced use of sales tax and other things. One can discuss the data series and their quality with the CSO...," he said.
According to Sanyal, a quirk in the "unofficial" back-series data produced a kink in 2002 which led to depressed growth rates up to 2002 but increased all rates after that. All methodologies for back-series data will have some quirk, he had earlier said.