Throughout the 1990s,
the results of the NSS "thin samples" on household consumption
expenditure generated much interest in both academic and policy circles.
These results, which suggested at an all-India level that rural poverty
did not show any declining trend over the 1990s despite higher rates
of aggregate GDP growth, were seen as important inputs into the ongoing
policy debate on the effects of the liberalising economic policies instituted
by successive governments over the 1990s.
Those who had been questioning
the economic reform package have pointed out that these policies have
led to a neglect of rural and agricultural investment, resulting in
reduced productive employment opportunities in rural areas and to higher
food prices, developments likely to be associated with persistent or
even increasing rural poverty. They pointed out that the evidence of
stagnation or even decline in rural non-agricultural employment was
also in conformity with the evidence of persisting rural poverty.
By contrast, proponents of the
economic policies of the 1990s suggested that the "thin samples"
simply did not allow for such conclusions, and that nothing could be
said about rural consumption or poverty until the next large sample
results were available. It was also argued by proponents of the official
economic reform strategy, that the NSS consumption expenditure estimates
from the thin samples were out of sync with the CSO estimates of GDP.
Thus they maintained that the association of higher GDP growth rates
with the persistence of rural poverty in particular was not a real fact
which needed to be understood and addressed, but more of a failure of
the statistical system to capture the actual consumption in rural areas.
With this background, obviously
the results of the 55th Round (1999-2000) of the NSS, which is the first
"large sample" since 1993-94, have been eagerly awaited. Now
that the round is complete and the data due to be released later this
year, it has also become evident that this NSS Round is important and
interesting for another reason. This is that in the 55th Round, a different
technique has been used to establish household consumption levels. The
basic change is in terms of a change in the reference period.
Since the 1950s, the NSS consumption
surveys have been using an uniform reference period of one month. Since
the interviews are evenly spread out over the year, problems of seasonality
were ironed out. However, in recent years the NSS has revived the issue
of whether a one week reference period is more suitable for determining
non-durable consumption than the one month reference period currently
This is not a new issue : indeed,
it is a question which has been of concern to the NSS since the very
inception of the surveys in the early 1950s. In fact, in the formative
years of the NSS, considerable attention was paid to the length of reference
period suitable for ascertaining the correct level of consumption of
different items of goods and services, and a special report was brought
out covering the period April 1951 to March 1954 on the suitability
of reference period.
Most interestingly, the NSS under
guidance of P.C. Mahalanobis had carried out a special investigation
into this very issue in March-April 1952, based on 1254 households of
76 villages of West Bengal. The households were divided into two groups.
For one group, consumption details were procured by actual weighing
of food items (clean rice, pulses, sugar and salt) by field staff. For
the other group, data collection was by questioning, and here again
the group was divided equally between those for whom the questions pertained
to a reference period of one week and those for whom the reference period
was one month.