CSA backdated

My ex partner and I split up in 2009. We have a daughter who was aged 14 at the time my ex was not contributing towards her upkeep. So around Twelve months later I contacted the CSA who decided that he should pay 19.00 per week. He has not paid anything since that date. She went to college after leaving school and is now in uni. I have managed to support her all this time but now that she is at uni I am struggling. Is there anyway I can still request backdated monies from him