Health Insurance premium raised $160 this year Is this Allowed?

I have a family health insurance plan with Aetna. The first year we had it it was $545 a month the next year it raised to $606 a month which we were not happy about but seemed $60 was not that much of a raise, now this year they just informed us that our plan will go from $606 a month to $765 a month, This sounds like robbery to me! Are they allowed to do that? Now we are going to cancel and switch to someone else. Does anyone have any suggestions on okay health insurance with a resonable premium. We are willing to pay a low deductible ($1000 or less) and low co-insurance(20% or less) We want a company that won't raise our rates 30% every year any suggestions would greatly help. We own our own business and this is just killing us between gas and insurance we may have to close down because we are not making any money. Please Help