How to calculate scintifically what percentage of our income should be spent on food rent medical expenses?

I mean how salaries are fixed? and how much a person should save out of his earnings after everyday expenses

How to calculate scintifically what percentage of our income should be spent on food rent medical expenses?
generally banks while sanctioning loans for housing, they adopt maximum of 55% of the total monthly income as repaying capacity for monthly repayment. (EMI)



so it is understood that in your income 45% can be allocated scientifically for meeting on food rent medical expenses according to banks.



long back i heared that if there is any misappropriation of funds by govt employees and after enquiry if the same is to be recovered from his salary, govt fixed norms to recover maximum 65% of the total salary only and remaining 35% need to be paid by cash to him to cover his monthly expenses.



from this it is understood that in your income 35% need to be allocated scientifically for meeting food rent medical expenses according to GovtHow to calculate scintifically what percentage of our income should be spent on food rent medical expenses?
salary 8000 to 10000 saving should to 20%

10000 to 20000 30%



20000 to 45000 30%



more than 45000 45%



it is the same calculation banks do it for calculating your eligibility for paying EMI

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