The two insurance providers participating in Vermont's health exchange have submitted their request for premium increases for 2015.

MVP Health Care is requesting an average 15.4 percent increase and Blue Cross Blue Shield of Vermont is requesting an average 9.8 increase.

MVP's proposal would increase the monthly, unsubsidized premium for a single person buying its silver plan by $76.84, or 18 percent, over the 2014 rate. The monthly cost of MVP's lowest-cost plan, the bronze, would increase $61.59, or 18.3 percent, under the proposal.

The cost of MVP's two high-deductible plans, silver HD and bronze HD, would go up the least at 10.7 percent and 10.8 percent, respectively.

For the six standard plans Blue Cross offers on Vermont Health Connect, monthly premiums would go up between $20 and $70 in 2015.

MVP's request cited the cost of prescription drugs among the reasons for the sharp increase, as did Blue Cross' filing.

"Sadly, the rapidly-rising price of health care services in Vermont, coupled with a sharp hike in prescription drug costs, federal taxes, and an enormous slash in federal reimbursement rates, make the economics of providing coverage unsustainable in 2015 without premium increases," MVP Interim CEO Karla Austen said in a statement.

Blue Cross Blue Shield of Vermont said the increase is needed to cover rising medical and pharmaceutical costs for its members and increased federal fees charged to insurers as part of the Affordable Care Act.

"... And since the factors driving this rate increase are almost entirely related to federal policy changes and increases in prices paid to medical providers in Vermont, there is no way to further reduce these rates without underfunding the health care coverage on which Vermonters rely," Blue Cross CEO Don George said in a statement released Monday.

In last year's rate review process Blue Cross' requests for exchange plan prices were revised down an average of 4.2 percent by the board.

The Green Mountain Care Board has 90 days to review and adjust the rate requests, which take effect Jan. 1.