"Under the current circumstances, something has happened that has made measurement (of GDP data) even more difficult for India. Basically what has happened is that because oil prices have come down, our CPI and WPI inflation have come down and that makes computing GDP data much more difficult," Subramanian at the India Today Conclave.
"There is going to be some uncertainty about (GDP) data, may be there is going to be more uncertainty about GDP estimates because of these factors," he added.
Asked whether he still considers new GDP calculation methodology 'puzzling', Subramanian said: "I think that the doubts that I had raised earlier were related to changes in methodology of estimation of GDP. I think now there are other sets of doubts about numbers.
"My response to that would be to look into all estimates. There is normal range of uncertainty. I think this happens in all countries around the world."
Last year, Subramanian had said that government's new GDP methodology is "puzzling" and had added that new numbers show growth to have accelerated during 2013-14 despite that being a "kind of bad year".
The earlier estimate of GDP growth for India for 2013-14 based on the basis of old series was 4.7 per cent.
These changes follow a revision in the base for calculating national accounts to 2011-12 from 2004-05.
The base year was last revised in January 2010.
Asked as to why Modi-led NDA government did not scrap retrospective tax amendment, Subramanian said: "This is really a big political decision that has to be taken. I think there might have been challenges and complaints that the government was trying to favour one foreign company."
Subramanian said India's perception is going to be determined by whole range of issues.