The finance ministry and Reserve Bank of India [Get Quote] have reservations on the computation of inflation data on a monthly basis, a senior government official said on Thursday.

"Everybody from the committee (on new WPI series) has supported moving to a monthly data, except for the Finance Ministry and RBI, which want it on a weekly basis," Ministry of Statistics and Programme Implementation Secretary Pronab Sen said.

Finance Minister P Chidambaram will have to meet the Reserve Bank to reach a consensus on the committee's suggestions to have a new series of WPI on a monthly basis, he said on the sidelines of a function to release the results of the Fifth Economic Census.

A committee, headed by Planning Commission member Abhijit Sen, that is formulating the new WPI series has advocated a monthly release of data with a two-week lag, Pronab said.

Professing the need for a monthly data, he said weekly figures on wholesale prices released by the government creates huge volatility in both commodities and stock markets.

"Every body is reacting to the current weekly rather than the revised figures, which are a month old, and that creates volatility that is completely unnecessary," Pronab added.

The Abijit Sen committee is expected to submit its report soon. The new series is likely to have a base year of 2004-05 instead of 1993-94, which is followed at present, and the number of items covered under the index would be increased to 900 from 450.

"Increase in the number of items would make the WPI more comprehensive," Pronab added.

The government, in due course also plans to move towards a Producer Price Index, comprising the Wholesale Price Index and the proposed Service Price Index.

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