Exactly right. I first coded in Fortran in the mid 80s on a mech eng code base written in Fortran 66. Fortran 77 was avoided because it was too new. In the early 90s I worked in reservoir engineering where we used 77. Fortran was the choice for number crunching, especially on hardware like Crays that used vector processors that could be exploited by specialised compilers. Those early Fortrans had very little in the way of abstraction. Data was passed around in 'common blocks', and there was no dynamic memory allocation. Remember that Bloomberg started in the 80s. So it's likely that they have a huge Fortran codebase in one of these old variants of the language.