From 1815 the East India Company required its district officers in the Bengal Presidency to report every case of widow immolation to the Nizamat Adalat. The returns ran until the practice was prohibited in 1829, and they record 8,134 cases across those fourteen years.
That number is quoted constantly and is almost always quoted wrongly, as though it were the rate at which sati occurred in India. It is not. It is the number of cases that a particular administration, in one presidency, over fourteen years, managed to hear about and chose to write down.
The internal evidence that the series is a record of reporting rather than of practice is in the geography. More than half the recorded cases fall in the Calcutta division, in and around the seat of the administration doing the counting, and that is not where the practice is otherwise understood to have been concentrated. Two readings are possible, and both are held: that the division genuinely had an unusually high incidence, or that the returns are densest where the Company had the most officers and the strongest interest in the answer.
The returns also had a purpose. They were compiled while the question of prohibition was live, by an administration under pressure from evangelical opinion at home and from Indian reformers in Calcutta, and they became the evidence on which the case for prohibition was argued. A count assembled inside an argument is not thereby false, but it is not an innocent measurement either.