DateTime sucks

# of iterations = 100,000
null_time                                            =  0.01s
Time.parse(s)                                        = 22.64s
DateTime.parse(s)                                    = 43.75s
DateTime.civil(*Time.parse(s).to_a.first(6).reverse) = 35.22s

Unless you're doing geology or astronomy... try to stick to Time.