The scheme has only been going for two years, so yes it would be worth checking again after say 10 years.
But there are significant differences. From the Wikipedia article:
> Indeed, fatal car-to-car and car-to-pedestrian accidents dropped sharply as a result, and the number of motor insurance claims went down by 40%.
> These initial improvements did not last, however. The number of motor insurance claims returned to 'normal' over the next six weeks and, by 1969, the accident rates were back to the levels seen before the change.
So those results returned to normal over 6 weeks, but the shared spaces were measured over 2 years. Also the changes were more drastic. 36 accidents over 4 years (9 per year) vs 4 over 2 years (2 per year).
But there are significant differences. From the Wikipedia article:
> Indeed, fatal car-to-car and car-to-pedestrian accidents dropped sharply as a result, and the number of motor insurance claims went down by 40%.
> These initial improvements did not last, however. The number of motor insurance claims returned to 'normal' over the next six weeks and, by 1969, the accident rates were back to the levels seen before the change.
So those results returned to normal over 6 weeks, but the shared spaces were measured over 2 years. Also the changes were more drastic. 36 accidents over 4 years (9 per year) vs 4 over 2 years (2 per year).