A more proximate example of this phenomenon is the recent controversy on the Gross Domestic Product (GDP) calculations from 2004 to 2011 period done by the Central Statistics Office (CSO). Let us examine some of the facts that underline this debate. It is well known that data pertaining to the informal or household sector in India is limited and often available with long time lags. The principal sources of data for the household sector in India are National Sample Survey Office's (NSSO) sample surveys of household and establishments, usually done at an interval of five years. In this case, NSSO had done household surveys of employment in 2004-05 and 2011-12, and surveys of establishments had been done in nearby periods. What emerged from these were some very striking facts. One, which was was widely noted by experts and commentators, was that between 2004-05 and 2011-12, we had one of the slowest growth rates in labour force. Its implications, however, for India’s GDP computation were not equally appreciated by most. Since the GDP base was revised to 1999-2000, the CSO would compute the benchmark estimate for value added in the household or informal sector by combining labour force estimates from household surveys with labour productivity estimates from establishment surveys. The benchmark estimate would then be projected in non-survey years by indicators that were more regularly available, or by simply extending the growth profile from earlier benchmark calculations. Slow growth in labour force means that under this method, the value added in 2011-12 had been over-estimated. The extent of over-statement would have been almost 100 per cent. In other words, the actual value added in the informal sector was almost half of what had originally been computed. A fact that most critics on the new GDP series conveniently ignore is that, if the methodology and other data sources had not been revised, we would have needed to revise our GDP estimate for 2011-12 downwards by almost 25 per cent. Its consequential impact on the growth between 2004-05 and 2011-12 can be similarly evaluated.