Govt on Wednesday strongly defended the sanctity of GDP dataNEW DELHI: Govt on Wednesday strongly defended the sanctity of GDP data, and argued its critics' arguments are flawed. Critics pointed to the revision in nominal GDP number in Q1 FY 25-26, the base period for calculating this FY's QI growth rate. Govt said the revision was consistent with the new methodology. The base year has changed, the use of producer price index provides more granular information, and more data is available. This led to the revision, which is completely kosher, govt said.The statistics ministry said Q1 GDP estimate for 2025-26 was lowered from Rs 86 lakh crore to Rs 80 lakh crore as it was based on earlier series (2011-12 base year), which has now been updated to 2022-23.Former finance secretary Subhash Chandra Garg had said nominal GDP growth would have been about 2.6% during April-June 2026-27 and real GDP growth close to 0% if last year's GDP had not been revised down from Rs 86 lakh crore to Rs 80 lakh crore.‘Going forward, no substantial revision in GDP no.s expected’The statistics ministry said Wednesday GDP numbers from different series cannot be compared to arrive at the growth rate. Accordingly, GDP at current prices under the new series was estimated at about Rs 80.3 lakh crore for June quarter of the last fiscal year.This was revised to Rs 80.4 lakh crore in June because of the availability and updation of indicators and data. As the new series of Index of Industrial Production (IIP) and PPI became available and were incorporated into the GDP compilation, the first quarter GDP at current prices for 2025-26 was revised to Rs 80 lakh crore, it said.On Monday, govt released growth figures for Q1 FY 2026-27 which also saw revisions in both the preceding quarterly and annual figures. For example, growth for Jan-March quarter of financial year 2025-26 was revised upwards to 8.6% from the provisional estimate of 7.8%. Similarly, annual growth in 2023-24 is now estimated to have been 7.3%, up from 7.2%, while a similar 10-basis-point (bps) upward revision has been made for 2024-25 and 2025-26 to 7.2% and 7.8%, respectively.On Wednesday, statistics secretary Saurabh Garg told reporters that quarterly estimates are largely based on indicators and are revised as more comprehensive information on corporate performance, govt activity and actual output becomes available, whereas annual figures are generally more robust.“There is no consistent upward or downward bias in the new series as some quarters had been revised higher and others lower,” he said.Going forward, no “substantial” revisions in GDP figures are anticipated, barring a few basis points, he added. “The earlier series relied on around 180 deflators, while the new methodology uses more than 300. The greater granularity allows to undertake double deflation more comprehensively across the manufacturing sector,” Garg told reporters.Under double deflation, output and the inputs used in production are deflated separately to arrive at real value added.