He said NSSO data shifted the base year which is not unusual but the CSO data shifted the base year gave up RBI data base and switched over to Ministry of Company Affairs data base called MCA-21.

"Now MCA-21 is not being made available to anyone in the public domain - not available to economists - not available to researchers. It is a closely guarded secret of the government. They are using MCA data to get information about companies, their production, their profit," he said at a press conference here.

Chidambaram said NSSO, in the surveys, that was underway, completed, has found 35 per cent of companies in the MCA data base do not exist, they are not traceable.

"They are either closed down or they not found at the addresses they have given. So, what is the data you are using to fool the people of this country that the GDP growth is much higher than the UPA? This is a scam. This is a scandal which has to be investigated first before we find solution of it," he said.

He said the BJP-led government is leaving behind only problems.

"We have to address every single aspect of the economy - growth, fiscal stability, sluggish imports and exports, rising Current Account Deficit, fall in investments, fall in consumption expenditure and steep decline in agricultural growth and services sector growth," he said.

The Congress leader alleged that the political leadership had interfered in an area which was normally beyond limits.

"You don't interfere with the CSO's working. The political leadership has virtually captured or intimidated the CSO and NSSO. You saw two of the only remaining officers resign. So, it is entirely the blame that has to be laid at the door of the political leadership, whose approach has been to capture and intimidate institutions," he said.

He said howsoever much Prime Minister Narendra Modi wants to take away the narrative from the economy, ultimately, people will vote on the state of the economy.

Doubts about veracity of the new series of GDP launched in 2015 have resurfaced after a new National Sample Survey Office (NSSO) report showed that around 39 per cent of companies in the MCA-21 database, used for GDP calculation, could not be traced or surveyed.

"Out of the 39 per cent out-of-survey units in MCA, 21 per cent were found to be out of coverage and another 12 per cent were non-traceable (which in number is nearly 4,000 units)," said the report.

These companies were described as "active" companies by the Ministry of Corporate Affairs.

This revelation casts further shadow on the new series of GDP data, which had showed significant drop in the growth estimate for the UPA administration.

The usage of MCA-21 data was started with the new series in 2015, instead of the previous data taken from the Reserve Bank of India. Several statistians and economists have raised concerns over the accuracy of the data since its inception.