Inside Money: Cat calculations (or dirty deeds done dirt cheap)

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Stella had just begun reading chapter six of Curiosity by Philip Ball when she decided to disestablish the cat.

The cat's waveform, as a quantum physicist might put it, was collapsing. And so were her legs.

Briefly, Stella considered whether Curiosity would do the job. At 460-plus pages the book carried plenty of heft but, as she only had the paperback edition, Stella opted for a more conventional approach.

"I need to put some science around this," she thought, drawing on her investment knowledge to calculate the net present value of her cat.

On the plus side, Stella listed:

- Ongoing rodent prevention services;
- Child amusement abilities;
- Potential health benefits - of purr;
- Sense of connection with 'nature'.

Offsetting the benefits, she itemised:

- Regular food bills;
- Litter management risks;
- Escalating healthcare costs;
- Projected increase in carpet-cleaning expenses;
- Possible threat to native wildlife;
- Annoying Gareth Morgan (although in some models this is factored as a positive).

No matter how she manipulated the factors (within reasonable parameters), which were output as a 'discount rate', her cat spat out a negative net present value - or 'vet present value'.

The vet concurred.

He gave Stella three options:

1) Death only - $70;
2) Death plus cremation (no ashes) - $90;
3) Death plus cremation (ashes supplied) - $150.

Taken aback by what, she assessed, as the unreasonable $60 surcharge for ash supply, Stella went cheap, selecting death-only.

It was a decision she came to regret the next day, when, after a difficult three-hour dig, Stella scooped up the last handful of loose soil from the cold ground in her improvised plastic bucket.

"Time is precious," she thought at the end, "maybe it's worth paying extra to outsource your dirty work."