public static IncomeTaxTableEntry CreateWith(decimal minThreshold,
decimal maxThreshold,
decimal accumulatedTaxFromPreviousBracket,
decimal marginalTaxRate)
{
EnsureValidValues(minThreshold, maxThreshold);
var incomeThreshold = CalculateIncomeThreshold(minThreshold);
var taxBracket = new IncomeTaxBracket(accumulatedTaxFromPreviousBracket, marginalTaxRate, incomeThreshold);
var taxTableEntry = new IncomeTaxTableEntry(minThreshold, maxThreshold, taxBracket);
return(taxTableEntry);
}
private static decimal CalcualteMarginalTaxableAmount(decimal yearlyTaxableIncome, IncomeTaxBracket incomeTaxBracket)
{
return(yearlyTaxableIncome - incomeTaxBracket.IncomeThreshold);
}
private IncomeTaxTableEntry(decimal minThreshold, decimal maxThreshold, IncomeTaxBracket incomeTaxBracket)
{
_minThreshold = minThreshold;
_maxThreshold = maxThreshold;
IncomeTaxBracket = incomeTaxBracket;
}
private static decimal CalculateMarginalTax(decimal yearlyTaxableIncome, IncomeTaxBracket incomeTaxBracket)
{
var marginalTaxableAmount = CalcualteMarginalTaxableAmount(yearlyTaxableIncome, incomeTaxBracket);
return(marginalTaxableAmount * incomeTaxBracket.MarginalTaxRate);
}