I think your question needs to consider statistical distribution of pay for that industry, thus in order to answer your question, you should first set a threshold of say, RM10k/month, and see which career has higher statistical probability of reaching that threshold.
Otherwise, the present question fails to answer any part on the likelihood (probability) of achieving the prior mentioned top of the salary curve. Which, for normal, average citizens such as ourselves, we are most unlikely to be at the top of the game. Thus, on this assumption, the more relevant question is, which career or job will result in the highest likelihood of achieving a target pay.
Perhaps, say, 5% of accountants make more than RM10k, but 15% of doctors make more than RM10k, so by the same argument, you should be a doctor. (only an example, please substitute real life figures into the above arguments)
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Subsequently, you should also consider the cost of investment to incoming cashflow on such career choices.
e.g.
A medical degree will cost RM100k per year for the first 5 years, whereas an accountancy degree will cost RM10k per year for the first 3 years. Assuming an inflation rate of 5% and you can finance both projects, but the both projects are mutually exclusive.
A medical degree, a doctor has a yearly cash inflow, (Net of tax) of RM100k, on an increasing by 5% (real rate of increase, aka net of inflation) every year. So using the annuity formula, assuming you will retire at 55, and you being your work career at 25, you expect to have positive cashflow for 30 years.
On the other hand, an accountant will have a yearly cash inflow of 40k, increasing 10% a year, and you will start work at 22, giving you a useful life of 33 years.
You can input both these 'projects' into an excel spreadsheet, discounting their future cashflows by inflation. Whichever project that results in the highest net present value should be your choice of studies.
highest pay of job in malaysia, doctor/pharmacist/nurse/accountant or..?