ISI Kolkata does not provide a B.Math program. The majority of B.Stat students return for M.Stat while some people join CMI, TIFR, IIM, and other such organizations. 

M.Stat employees earn an average of 16–17 LPA, and many of them attend prestigious US graduate institutions. There are no fees for the entire program, and a stipend is provided. So, if you're looking for a career here, your future is bright.