I have been saying this for 12 years while running my own law firm. Prior to that, I said it for almost a decade working for insurance companies. And yet, despite what I say, people do not listen. So let's try it again - there is NO formula for settling a personal injury case, whether it is a car accident, slip and fall or any other type of injury.
First, despite what some adjuster might tell you, and what you will read on the internet, there is no secret formula or book that tells you what your case is worth. Insurance adjusters are big now in telling people that they have reviewed the information and their formula tells them that the case is worth a certain amount. Heck, I heard it yesterday! Trust me, juries do not use formulas when they evaluate cases and good personal injury attorneys do not use formulas either.
Each case has its own value and the insurance companies alleged "formula" is not accurate. If it was simple as multiplying your medical bills by a certain number, a lot of people say 3 times your medical bills, then there would be a lot of unemployed attorneys, on both sides, and a lot of unemployed adjusters. Think about the money insurance companies would save by firing their adjusters. And, make no mistake, insurance companies like saving money! There is no formula for settling a claim as every claim is different and every situation is different!
The adjuster will also try to talk you out of retaining an attorney. The adjuster will tell you that it does not increase the value of the case. That is complete garbage. An attorney with experience can help you maximize your recovery. In fact, a study by Allstate, and confirmed by other insurance companies, showed that people who hired an attorney recovered more money than someone who did not hire an attorney. In other words, hiring an attorney resulted in a larger net settlement for the injured party. (By the way, add in that you have less stress, don't have to talk to the adjuster, and don't have to worry about missing some deadline and it makes more sense.) They just don't want to publicize these studies!
Talk to an attorney and find out the real value of your case. Do not assume there is a formula, despite what you might read online!