In September 2012, the Company purchased mobile construction equipment pursuant to financing arrangements whereby the equipment manufacturer provided payment terms of three years with no interest. As of December 31, 2012, the aggregate amount outstanding under these arrangements approximated $0.3 million, net of imputed interest at 4.25%, or an aggregate discount of approximately US$20,000. The underlying notes are collateralized by the equipment purchased.

Future scheduled principal payments under note agreements are as follows: