Final answer:
Singapore was likely just a small town with less than 1% of its current GDP around six decades ago, shortly after gaining independence in 1965. It has since become part of the East Asian Tigers, achieving phenomenal economic growth and complete urbanization.
Step-by-step explanation:
The question on how many decades ago Singapore was just a small town with less than 1% of its current GDP refers to a period before its significant economic transformation. Initially under British rule and part of the Malaysian Federation, Singapore gained independence in 1965. Since then, it has become an economic powerhouse, often included in the group known as the East Asian Tigers. This group saw average a growth of 5.5% real per capita for several decades, propelling Singapore to its current urbanized state with high-tech manufacturing and a major port for international trade.
In terms of the economy, Singapore's GDP has increased dramatically over the past few decades, particularly after the 1970s, in line with its rapid development and urbanization. Considering the incredible growth, it can be inferred that Singapore's status as a 'small town with less than 1% of its current GDP' would possibly pertain to a period shortly after independence, likely in the 1960s or perhaps a few years prior.
Given the substantial economic progress particularly since the 1970s, it is reasonable to suggest that the timeframe in question could be roughly six decades ago, as Singapore has undergone extensive economic development since the mid-20th century. However, without specific economic data from that exact time period, it is challenging to determine precisely when Singapore's GDP was less than 1% of its current value.