Year data and form not meshing

MySQL database year(4) field named 'built_year’
CakePHP 3.3 form $this->Form->input(‘built_year’, [‘type’ => ‘year’, ‘minYear’ => 1900, ‘maxYear’ => date(‘Y’)]);
$this->request->data[‘built_year’] contains [‘year’ => ‘1973’] but saves to database as 0000.

It works if I manually set $this->request->data[‘built_year’] = $this->request->data[‘built_year’][‘year’] in my controller (by the time it gets to beforeSave in the model $entity[‘built_year’] = ‘’) but I shouldn’t have to do this. Should not year form type map correctly to year(4) fields in the database?

Learn your mysql data types real good, if you are messing around with timestamps, DON’T. That’s why I use datetime field.
Timestamps are fine for tracking a record create or edit, I would use datetime or date fields for everything else.