Brexit torpedoed every nation's stock market except one

Greece, Spain, Italy, Ireland, and Namibia — all have felt the cool wind of Brexit coursing through their equity markets. 

Indexes based in those countries plummeted in the wake of Thursday's vote, and more so even than London's own FTSE 100 which had registered a 12 percent drop, by 2:20 p.m. on Tuesday.

Ireland's Overall Index dropped 16 percent and in currency-adjusted terms was the most affected of the 94 major equity indexes tracked by Bloomberg. 

While the only country with which the U.K. shares a land border suffered the most, it didn't suffer alone.

All but one major world stock market has lost value in the wake of the U.K.'s decision to leave the European Union which spooked investors in what, as of Thursday, was the world's fifth largest economy.

Only investors in Zambia's stock market came up on Tuesday smiling.

The Lusaka Stock Exchange All Share Index has gained a whole 2 percent since the votes were counted. 

"It's an economy and a market that's been badly beaten up in the past year. Usually the currency is more correlated with copper price than anything else," according to Charlie Robertson, the London-based chief economist at Renaissance Capital.

Now that Britain is no longer a commodity powerhouse, metal prices are relatively shielded from what happens in the U.K., and the fact they'd rebounded to pre-Thursday levels, by midday on Tuesday may have helped lift the index.

At the same time, the 21-company index is so small that it's extremely sensitive to purchase orders one way or the other.

"It could simply be one sizeable order by an investor trying to get into a stock would drive it up," Robertson said.

The index trades for just three hours a day.

So, the only index to gain since Brexit arguably has nothing to do with Brexit.