Error was caused by two things:
1) string objects do not have a trim method in IE8. It was used to parse the content of clicked row to populate the edition form input fields.
2) Object.keys() is not supported in IE. It was used when validating edited/created wage.

When clicking on a row of wages or worked hours tables, input fields appear, but on the following line and nothing can be saved. a javascript error occurs stating that Object does not have that property.