Of course they get it from government run agencies, but they interpret the data they get from them differently, & apply different standards on it. It's not about me what I want to believe or not, I just read about a couple of weeks ago that India overestimated its exports by $9 billion, it's overestimated its water availability, among many other things. So I am skeptical about the figures the Indian government puts out, but I am willing to accept them if the WB/IMF/UN quotes them in their report.
That was a software glitch and data entry error. If we go by that logic India also intentionally underestimates it exports.
As a result, data on engineering exports was inflated by around $15 billion, while export of gems and jewellery and petroleum products was underestimated by $12 billion.
For instance, the government had revised upwards the export numbers for 2008-09 from $169 billion, estimated originally, to $185 billion. Similarly, imports too were found to be $15 billion higher than the provisional numbers of $288 billion. In 2009-10, exports finally turned out to be $2 billion higher at $179 billion.
So yeah thats that. Besides I showed you the figure from KPMG too.