How to pass data through a data elememt with custom code using DTM?

I am trying to capture a value from an input box by through a data element in DTM. The problem i am having is, I do not know how to pass the data from the data element to the event rule etc. In other words when i captuer data ausing custom code in an event rule. I can capture it and immediately pass it to a variable like an s.prop or evar etc. but when creating a data element you cant send it to an s.prop or evar..

Here is my script.

$("input[name='loanAmount']").mouseleave(function(){ $("input[name='loanAmount']").val(); satellite.getVar('loanAmount'); return true; });