Impossible to say as insurance is tailored to your circumstances
Insurance went up about 30% in the last year which may account for your new quote
Best thing to do is try all comparison websites, adding your parents on as additional drivers and upping your excess. Keep ringing them for the best quotes.
Or do what Outrage has posted in the link above at your own risk:
Read this before or after you read Outrages link
http://www.saxperience.com/forum/sho...d.php?t=348350