Last week the Danish central bank started trolling me. Either that or it didn't read my last Ello (which I find frankly hard to believe). I refer of course to their move to follow the SNB through the looking glass into setting meaningfully negative interest rates, far through the Zero Lower
Anyway, I caught up today with @NevilleHill today and the ZLB and Vault Cash ETFs naturally came up. He put it to me that the cost of implementing such an ETF in Blighty might be somewhat costlier than in Switzerland. Think of the vault space required to house £100bn in £50 notes against the space required using CHF1,000 notes. And then what if the ETFs really took off and monetary authorities responded by increasing note size and reducing its denomination.
I loved this thought experiment because it ends with the imagery propagated by hyperinflationists: the Weimar-like prospect of paying for weekly shop with thick stacks of cash. But the spin is that the weekly shop costs exactly the same as it did before deeply negative rates.