Older is gooder

What is the lifetime cost to provincial government of a person?

Here is a stab at figuring that out for a Nova Scotia born and educated engineer.  My assumptions (using readily findable numbers) are:

Public School	12 yrs at	$15,000
Bachelor's Degree	5 years at	$9,000
health	birth	$11,000
	1-14 yrs at	$1,500
	15-64 yrs at	$2,700
	65+ at	$12,000
salary	start age 24	$50,000
	end age 64	$100,000
pension	80%, 3% COLA
NS income tax	15%

All in today's dollars and ignoring unknowables like HST,  Federal, and property taxes.

It's probably too simple, but you get the drift.  The province's investment is front end loaded and there is no return until the first job starts generating tax revenue.  Then there is gradual catch up and the province finally starts seeing returns at age 57.  After that, it's all gravy, even with high health care costs, and if our engineer has an average lifespan of 85 years, the province is $200,000 to the good.  I'd like to know what I'm missing.

It would be interesting to do this for others.

• A minimum wage worker
• A person receiving provincial supports

Ideas?