So close to Osaka: Why Shikoku, one of Japan’s 4 main islands, is losing population
An independent exercise, not a statement by the video creator or verification of every claim in the video.
Does more travel increase sales for local shops?
Suppose a bridge opens and a hypothetical region gets 120 additional visits from outside in one month, with 3,000 yen spent at local shops per visit. That adds 360,000 yen to local sales. If residents also make 80 extra trips outside and shift 6,000 yen of spending per trip from local shops, local sales lose 480,000 yen on that side. Together these changes reduce local sales in this example by 120,000 yen.
Check for yourself
- What data would show whether residents’ spending outside the region replaced purchases they would have made locally?
- How could improved access to hospitals be measured separately from shop sales?
Limits of application
This hypothetical calculation assumes all specified spending outside displaces local purchases. It does not estimate actual Shikoku sales or the bridge’s overall economic effects.
- What to look for
- See how Shikoku’s terrain and bridges shaped travel between regions.
- Why it matters
- When bridge trips increase, calculate additional spending in the region and spending that shifts outside it separately.
Timeline
8 segmentsThe video calls the movement of shopping or business toward larger cities a siphoning effect, while also noting better access to hospitals and jobs. More trips still leave open where travelers spend their money. Rail results vary by segment. JR Shikoku reported an operating surplus for the Kojima–Utazu crossing in fiscal 2024 after including shared costs.