Azure PowerShell statement to find the earliest deployment in each resource group in a subscription

Get-AzureRmEarliestDeploymentsByResourceGroup

# Assumes the Azure RM context is already set (logged in, subscription selected).
# Returns a list of Resource Group Names and the Earliest Timestamp (from deployment activity) for each.

((Get-AzureRmResourceGroup | Select-Object ResourceGroupName) | Get-AzureRmResourceGroupDeployment)`
    | Select-Object ResourceGroupName, @{Name="Created"; Expression = {$_.Timestamp}} `
    | Sort-Object ResourceGroupName, Created `
    | Group-Object ResourceGroupName `
    | Select-Object Name, @{Name="EarliestTimestamp"; Expression={`
        $_.Group.Created | Measure-Object -Minimum | Select-Object -ExpandProperty Minimum `
      }}