Don't forget that there are fees to be taken into account as well but that does seem to be a lot of money for a comparatively small debt.
Which company are you with?
Sharing from experiences of dealing with debt
The greatness of a man is not in how much wealth he acquires, but in his integrity and his ability to affect those around him positively.
Bob Marley. http://kallis3.blogs.iva.co.uk
By year 3 you may have paid 100p in the £ so check with your IVA company what happens at that stage.
It is likely that you will complete early.
IVA started March 2011, Completed March 2016 and certificate issued 11 days after final payment. It was not always easy but then some of the best decisions aren't.
An IVA might not have been the best plan at the outset with that level of debt and repayment. However, on the plus side it has frozen ongoing interest and it looks like you should finish early.
My opinions are merely that .. opinions based on experience. Always seek professional advice.
IVA Completed 23rd July 2013 .... C.C. 10th January 2014