I studied business science in professional accounting. This was never my first passion. I always wanted to study applied mathematics. 
Due to my degree, I got a job as a finance assistant. The company that I am working for is a insurance company.
I am currently pursuing my honors in Data Analytics and will hopefully enroll in a masters in Data Science. The company does have a need for analytics, however, they do not have the department or tools to aid a role in data analytics. I have recently been part of the IBNR calculation and I find I enjoy the analysis side. My desire is to be a data scientist, thus me pursuing my studies. 
Currently I have been made an offer from a external company to be a financial accountant, but the salary is more than double than what i am currently earning. The salary will allow me to gain financial independence, however, the field, being Accounting, is what I hate. 
How could I tell me boss that I have been made this offer but i am on the fence about it due to it being a financial accountant role, however, the salary will more than benefit me. I enjoy the insurance analysis but my current position is a finance assistant and my salary is poor. 