Compute invoice penalty amount

penalty_compute.rb

require 'date'

puts "Enter due date (YYYY/MM/DD) : "
due_date = gets.chomp
puts "Enter amount VAT included: "
amount = gets.chomp.to_f.round(2)
puts "Enter penalty rate : "
penalty_rate = gets.chomp.to_f.round(2)

penalty_amount_by_day = (amount * penalty_rate / 100.00) / 365
penalty_amount_today = penalty_amount_by_day * (Date.today - Date.parse(due_date))

puts "Penalty amount by day : #{penalty_amount_by_day}"
puts "Penalty amount for now : #{penalty_amount_today}"