A delay in holding India’s census has impacted the quality of all statistical surveys, including economic data, inflation and jobs estimates, said the head of a government panel set up to review the surveys and suggest improvements.

India’s once in a decade census was due to be completed in 2021 but was delayed because of the Covid-19 pandemic. Technical and logistical hurdles have caused further setbacks and the mammoth exercise is unlikely to start soon.

Last week, the government expanded the term of a government committee on economic surveys by two years, renaming it the Standing Committee on Statistics, and asked it to review survey methodologies, sampling design, and steps to identify data gaps.

“The quality of any statistical survey depends on census data,” Pronab Sen, the head of the renamed Standing Committee and a former chief statistician of India, told Reuters in an interview on Wednesday.

In the absence of the latest population census figures, which capture household data on employment, housing, literacy levels, migration patterns and infant mortality, the government statistical surveys were still based on the 2011 census, Sen said.

India’s Economic Advisory Council to the Prime Minister alleged earlier this month that survey reports were underestimating growth estimates and the impact of welfare measures on poverty alleviation.

“No one can say that data is perfect,” but criticism by some economists in public “raised doubts about their intentions” as they could have raised it internally while suggesting ways to improve the quality of data, he said.

In 2019, India put on hold on the release of the national consumption expenditure survey for 2017/18, which is usually released every five years, over quality issues. That has delayed changes in the base year for data used in the consumer price index and gross domestic product surveys, which are still based on 2011/12 data.

Sen said the Standing Committee would consider steps on improving survey data quality in the absence of census data, which is unlikely to be available for the next two to three years.