Concern over ethical investment practices - including revelations scheme providers were potentially legally opposed by investing in banned weapon-makers - saw KiwiSaver churn numbers spike over the past two months.
According to the latest monthly data on the scheme provided by Inland Revenue, 13,250 people changed schemes in August and 15,064 in September.
This compares with an average monthly churn of 11,489 in the ten months preceding, meaning the recent surge amounted to a 23 per cent increase - or 5,317 more people - changing schemes.
Assuming those switching scheme had the average account balance of $11,500 for all contributors, this represents a movement of funds worth $61.1m.
The Herald and RNZ revealed in August that KiwiSaver fund managers had invested $153m of client funds in stocks blacklisted by the government-run New Zealand Superannuation Fund. These investments included $43.4m of potentially illegal investments in companies making weapons banned by New Zealand legislation.
The matter was looked at by Police and the Financial Markets Authority, and while a decision was made not to investigate providers for criminality, the subsequent lightning reform of the sector has drawn international attention.
Within two months $109m of identified controversial stocks had been dumped by KiwiSaver providers - including 99.9 per cent of investments in the banned weapon-makers - with attention turning how to manage exposure to such firms held indirectly through index investments.
The increased churn levels, representing KiwiSaver clients dissatisfied over the former status quo taking their business elsewhere, at least partly explains the swift action.
Along with providers divesting direct holdings in controversial companies, concern by fund managers over the issue prompted giant international provider Vanguard Funds to establish a tailored New Zealand-focused fund excluding landmine, nuclear weapon, cluster-bomb and tobacco-makers.
The move would possibly to see a significant shift in capital, with KiwiSaver providers having invested billions into broad international index funds in order to secure global exposure.