What year did IALA have 30 dissimilar buoyage systems in use worldwide?

The year 1976 is significant in the history of maritime navigation systems because it is when the International Association of Lighthouse Authorities (IALA) recognized that there were approximately 30 different buoyage systems operating around the world. This situation highlighted the need for a standardized buoyage system to enhance maritime safety and navigation efficiency. As a result of this recognition, IALA initiated the process to develop a unified system, which eventually led to the adoption of the IALA Maritime Buoyage System we have today. By standardizing buoyage systems globally, IALA aimed to eliminate confusion and improve safety for mariners navigating in different regions.