Taxes Estimator 2012

taxes.rb

SINGLE_RATES = {8700 => 0.10, 35350 => 0.15, 85650 => 0.25, 178650 => 0.28, 388350 => 0.33, Float::INFINITY => 0.35}
MARRIED_RATES = {17400 => 0.10, 70700 => 0.15, 142700 => 0.25, 217450 => 0.28, 388350 => 0.33, Float::INFINITY => 0.35}

def taxes(amt, rates=SINGLE_RATES)
  last_cap = 0
  taxes = 0
  rates.each do |cap, rate|
    taxable = amt - last_cap
    if taxable > 0
      taxes += [cap, taxable].min * rate
    end
    last_cap = cap
  end
  taxes
end