I have just installed the latest version of Yii through composer that is Yii2.0.40. And I have checked my composer.json and there version is not updated.
In composer.json it is showing 2.0.14
“require”: {
“php”: “>=5.6.0”,
“yiisoft/yii2”: “~2.0.14”,
“yiisoft/yii2-bootstrap”: “~2.0.0”,
“yiisoft/yii2-swiftmailer”: “~2.0.0 || ~2.1.0”
},