Bitcoin's disappeared from unused wallet
Looks like the tx you are referring to on 2014-03-24, sent the money to 

14N9ydxNRhDxkKJvXg1vjqS3gh884vG3UM - (Unspent) 0.039 BTC
1L9Q6EFMH3jn4dWquC2DaWhWK4q4pyUvum - (Unspent) 0.00060405 BTC

They both remain unspent.
1L... address is most likely the change address, that belongs to your wallet, if that transaction was made from your wallet.   

Someone could have gotten your private key and moved the money that way.
Since the money has been not spent there is not much you can to in terms of tracing.