inflation.js

// Compound interest
// Compound interest increases as a certain percentage
// of the principal each year. This gives us the formula


const compoundInterest = ({principal, ratePercentage, time}) => {
    return principal * ((1 + ratePercentage/100) ** time);
};
const initialAmount =({finalAmount,ratePercentage, time })=> {
    return finalAmount/((1 + ratePercentage/100) ** time);
}


compoundInterest({principal: 1, ratePercentage: 10, time: 7});
// initial   buying power in a year
let principal = 1200000;
let fdInterestRate = 5;
let inflationRate = 7.8;

// the target buying power you want as interest from your savings. This is your  income at the end of 10 years
let targetInterest =  compoundInterest({principal: principal, ratePercentage: inflationRate, time: 10})
// the above income should come as interest from this final accured amount
let finalAccuredAmount = targetInterest * 100.0 /   fdInterestRate;

// to get this final accured amount you need to have atleast this amount in bank at the moment.
initialAmount({finalAmount: finalAccuredAmount, ratePercentage: fdInterestRate, time: 10})