In 1921, the strength of the Scheduled Castes was 12 lakhs. Then, there is a big gap in 1931. Because the garden labourers were considered as depressed classes in 1921 but in 1931 they were separated from the depressed classes and considered as a single caste that is the garden cooly caste. That is why, in the census of 1931, their strength came down from twelve lakhs to six and a half lakhs. In article 155 of that Report dealing with the difficulties of return of caste, the Census Superintendent said : “When it comes to castes like the Kayasths, Mahisyas, and Patnis, I confess that the figures appear to me to be worthless and not worth the trouble of collecting.” In the same page, he again said : “When we came to castes like the Patnis in the Surma Valley, we find that at each successive census their numbers have been melting away in a most mysterious fashion.” That shows that the 1931 census could not give the accurate or correct figures of the Scheduled Castes people, and also indicated a gradual decrease in the number of the Scheduled Castes.
