Moving Average in DAX / BISM Tabular

Alberto Ferrari already wrote about calculating moving averages in DAX by using a calculated column. I'd like to present a different approach here by using a calculated measure. For the moving average I'm calculating a daily moving average (over the last 30 days) here.

For my example, I'm using the PowerPivot workbook which can be downloaded as part of the SSAS Tabular Model Projects from the Denali CTP 3 samples.