You could even include this in the model so that you can use it in other places:

```ruby
class Building < ActiveRecord::Base
  def self.states
    ["AK", "AL", "AR", ..., "WY"]
  end

  validates :state, presence: true, inclusion: { in: Building.states }
end
```

And then in the model spec:

```ruby
describe Building do
  it { should ensure_inclusion_of(:state).in_array(Building.states) }
end
```

And also in the form:

```HTML+ERB
<%= simple_form_for @building do |f| %>
  <%= f.input :state, collection: Building.states %>
  # ...
``` 

It reduces the need to copy and paste the states all over the place, making the code more DRY.