First stage: simple SJT and basic data based calculations. Second stage: Video interview Third stage: Written exercise with verbal and numerical analysis involved. Written exercise requires you to respond to colleague's email, but there are a lot of questions/dicussion points you have to answer in the email. Make sure that you answer ALL of the questions with decent effort on each. My mistake was spending too much time analysing numerical analysis questions in the beginning, and neglecting the general (seemingly insignificant) questions. The questions are all important for evaluation.