Coefficient of grandparents

I'll start by saying this is not really a coefficient, which implies multiplying and producing a figure between 0 and 1, but rather, involves adding. Much easier.

My grandparents have the figure of 88. Why? Because they died when I was respectively 2, 12, 34 and 40, which adds up to 88. In other words I had 88 years' worth of grandparents, while I was alive.

An interesting contrast is the figure for my great aunt Hilda (name slightly changed). Her figure is extremely low, in fact possibly as low as the figure can ever be. It is MINUS 80. Her grandparents died 2, 15, 28 and 35 years before she was born. This came about for two reasons: firstly that she was the youngest grandchild born when both parents were well on in their forties (and both parents had lots of older siblings as well); secondly the grandparents (who would all have been at least in their eighties) were from a different generation and all suffered some form of childhood loss, or in one case extreme poverty.

When I think of my meeting with aunt Hilda (born 1916), I cannot believe her grandparents belonged to such an early epoch, for instance
* her grandmother was orphaned in 1844 (and the wrong side of the Pennines to boot)
* her grandmother features in the will of Lancelot Gibson (b. 1785), who flourished as estate manager in northern Northumberland in another era
* her grandfather, a bit of a charmer, was the cause of Joseph Carline re-writing his will in 1856 (although this will never went to probate)
* her grandmother died only a hundred years after her great-great-great-grandfather, John Brasier, who kept rabbits at Checkhill Common, Kinver passed away in the 1790s
* when her grandmother was orphaned, in 1844, and brought back across the Pennines, her Scottish great-grandmother was then still living (but where was she from?)
* when her eldest grandparent was born, George IV was still on the throne (whose great-uncle was tutored by Edmond Halley that 'invented' Halley's Comet)
* her grandfather was the result of the marriage of the children of two brothers from a hat-making family in Derbyshire, born in the 1780s. One, careful, organised and wealthy. The other, disorganised, dissolute and poor.
* her grandmother, whose illegitimate birth has caused me much consternation, allegedly sat in 'that chair over there'

I would be interested to hear if her record of 'coefficient of grandparents' can easily be matched.