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I remember sitting next to a managing director on a business flight in the late 1990s. The stock market was recovering after the chaos of Russia’s debt default and the collapse of the Long-Term Capital Management hedge fund, and investment bankers were feeling bullish.
At one point, the MD leaned over and confided what he called his Number. This was the amount of money he calculated would let him leave investment banking for good. For him it was $15mn, excluding his home. He walked me through his logic, line by line, down to the cost of roof repairs every 10 years.
To me, a young banker with a family and a mortgage, it sounded absurd. How could anyone need so much, especially with a house in reserve? But for my travel companion, the Number represented a carefully planned target that would guarantee freedom.
Two decades later, the managing director left the industry and returned to his home country in Europe. I don’t know whether he reached his Number, but I’ve since understood that his fixation wasn’t unusual. The idea of the Number runs deep in finance. Bankers rarely discuss it openly, but almost all have a figure in their head.
Many workers estimate their retirement needs using the “4 per cent rule”, which suggests withdrawing 4 per cent of total savings in the first year of retirement and adjusting that amount annually for inflation. This approach is designed to provide steady income for 30 years.
For the average investor, it’s a passable framework for retirement planning. Financiers, however, see it as simplistic, failing to account for life changes and market fluctuations.
No matter how much they have, many bankers feel a deep, nagging sense of financial insecurity. Over the years, I’ve heard all kinds of Numbers, but they tend to share two traits: they are way more than will ever be spent in retirement, and they usually demand another five years of full-time work.
This ingrained caution stems not from old-fashioned avarice but from three sources: the culture of the finance industry; the lived experience of market volatility; and the stealthy creep of lifestyle inflation.
The work culture of finance institutionalises insecurity. Management actively works to keep you off balance: one of my bosses preached the mantra “destabilise to get better”, while another instructed me to draft a succession plan “in case you fall under a bus”. And even when we’d win a deal, any celebrations were tempered by the knowledge that our competitors would redouble their efforts to snatch away future business. After years of being conditioned to stay on edge, it is hard to shed that mindset once you leave.
Then there are the scars from market volatility. Financiers know how suddenly even the most diversified portfolio can devalue. They have seen stocks slide, bond spreads blow out, defaults surge, property prices collapse. Inflation and currency depreciation can ravage supposed safe-haven assets such as cash and government debt. And so-called stores of value offer little shelter: crypto prices swing wildly, and gold and silver crashed after their 1980 highs. Many bankers also saw their deferred compensation evaporate in 2008, as restricted stock units became near-worthless — an experience that cast a long shadow.
A third, subtler factor also feeds the conservatism: expenses have a way of expanding with income. Busy professionals outsource convenience — nannies, private tutors, cleaners — and justify it as a trade-off for long hours. School fees, club memberships and expensive holidays become routine. One retired friend told me he was shocked at how much he had been spending on gardening alone. When life runs at that burn rate for decades, it is hard to dial back. The lifestyle turns from a choice into a fixed cost.
That is why the Number isn’t really about money — it reaches into the deepest crevices of human psychology. For some, it means continuity: preserving a standard of living they are loath to relinquish. For others, it offers protection from financial anxiety or ruinously bad luck, like long-term care or an acrimonious divorce. And for a few, it promises a new beginning. Like in Collateral, where the taxi driver played by Jamie Foxx dreams of the Maldives, the appeal lies as much in imagining the escape as in actually living it.
In truth, no Number fully insulates anyone from life’s vicissitudes. Markets crash, health fails, taxes rise, wars and pestilence break out. For all its supposed precision, the Number is just a story we tell ourselves to pretend we have agency over randomness and entropy.
Maybe Douglas Adams had the best Number: 42, which was offered as the “answer to life, the universe, and everything” in The Hitchhiker’s Guide to the Galaxy. Because no Number can promise security. Life offers no safe spaces and no risk-free returns — just the illusion of control, priced to perfection.