Cannot inject $element into my controller

Hello. I am trying to follow the example LineChart from the amCharts example page. I have made my controller exactly like the LineChartCtrl, but the problem I have is that I get an error on trying to inject $element into my controller. It works on LineChartCtrl. I cannot understand why!

`angular.js:14199 Error: [$injector:unpr] Unknown provider: $elementProvider <- $element <- AssetChartCtrl
`

Can somebody please point me in the right direction to solve this?

Thanks.