A long time ago somebody created a spreadsheet "Quiz_CLtoMoodleXML_V.1.3.1_test". With this spreadsheet you can create all kind of questions in Excel and generate a Moodle XML file that can be imported into Moodle resulting in new questions in your question bank.
I've made a spreadsheet that can do this for calculated questions.
You can find more information here https://sites.google.com/site/cq4mgenerator/.
Let me know your comments.
I'll be presenting this work on Moodle Research 2013 and I hope to meet you there.