That being said, there probably is also a cultural element. I wouldn't really say it was a cultural shift. It's more that the relative stability and increasing globalization in the latter half of the 20th century gave Singaporeans the opportunity to realize their entrepreneurial ambitions.
New Zealand is so isolated that there's an entire continent between them and "through traffic" shipping lanes.
This is in addition to their 'legal' tax avoidance-derived GDP. In 2012, Apple did $14 Billion in revenue in Singapore, which was more than they had in the rest of Asia combined, yet they didn't have a single store or manufacturing center in the city-state.[2] Microsoft actually beat Apple to setup a Singapore-based affiliate for the same purpose.
I'm curious to see how they fare in a decade after these sources of 'income' are greatly restricted in the global crackdown.[3]
One of these days, I'm going to devote a few hours to calculating how much of Singapore's GDP / Tax base only exists due to their status as a tax haven.
[1] - http://www.icij.org/search/node/singapore
[a] - http://globalnation.inquirer.net/95743/pnb-gets-marcos-loot-...
[b] - http://www.icij.org/offshore/mugabe-crony-among-thai-names-s...
[c] - http://www.icij.org/offshore/billionaires-among-thousands-in...
[d] - http://international.sueddeutsche.de/post/74093618828/chinas...
[e] - http://www.smh.com.au/news/business/singapore-a-friend-indee...
[f] - http://www.ft.com/intl/cms/s/0/036282b4-be65-11de-b4ab-00144...
[2] - http://www.reuters.com/article/2013/11/24/us-singapore-tax-i...
[3] - http://www.spiegel.de/international/world/the-singapore-bank...